diff --git a/CHANGELOG.md b/CHANGELOG.md
index e0b47ff5e8..7e3215dc6c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@
 - Feat: 設定の管理が強化されました
   - 自動でバックアップされるように
 - Enhance: プラグインの管理が強化されました
+- Enhance: テーマ設定画面のデザインを改善
 - Fix: テーマ切り替え時に一部の色が変わらない問題を修正
 
 ### Server
diff --git a/locales/index.d.ts b/locales/index.d.ts
index 0cdd428c82..1f06e25f1e 100644
--- a/locales/index.d.ts
+++ b/locales/index.d.ts
@@ -7746,6 +7746,10 @@ export interface Locale extends ILocale {
          * 標準のテーマ
          */
         "builtinThemes": string;
+        /**
+         * サーバーのテーマ
+         */
+        "instanceTheme": string;
         /**
          * そのテーマは既にインストールされています
          */
diff --git a/locales/ja-JP.yml b/locales/ja-JP.yml
index 1e41c43864..9b3a051f0b 100644
--- a/locales/ja-JP.yml
+++ b/locales/ja-JP.yml
@@ -2031,6 +2031,7 @@ _theme:
   installed: "{name}をインストールしました"
   installedThemes: "インストールされたテーマ"
   builtinThemes: "標準のテーマ"
+  instanceTheme: "サーバーのテーマ"
   alreadyInstalled: "そのテーマは既にインストールされています"
   invalid: "テーマの形式が間違っています"
   make: "テーマを作る"
diff --git a/packages/frontend/src/components/MkThemePreview.vue b/packages/frontend/src/components/MkThemePreview.vue
new file mode 100644
index 0000000000..5b180b3680
--- /dev/null
+++ b/packages/frontend/src/components/MkThemePreview.vue
@@ -0,0 +1,96 @@
+<!--
+SPDX-FileCopyrightText: syuilo and misskey-project
+SPDX-License-Identifier: AGPL-3.0-only
+-->
+
+<template>
+<svg
+	version="1.1"
+	viewBox="0 0 203.2 152.4"
+	xmlns="http://www.w3.org/2000/svg"
+	xmlns:xlink="http://www.w3.org/1999/xlink"
+>
+	<g fill-rule="evenodd">
+		<rect width="203.2" height="152.4" :fill="themeVariables.bg" stroke-width=".26458" />
+		<rect width="65.498" height="152.4" :fill="themeVariables.panel" stroke-width=".26458" />
+		<rect x="65.498" width="137.7" height="40.892" :fill="themeVariables.acrylicBg" stroke-width=".265" />
+		<path transform="scale(.26458)" d="m439.77 247.19c-43.673 0-78.832 35.157-78.832 78.83v249.98h407.06v-328.81z" :fill="themeVariables.panel" />
+	</g>
+	<circle cx="32.749" cy="83.054" r="21.132" :fill="themeVariables.accentedBg" stroke-dasharray="0.319256, 0.319256" stroke-width=".15963" style="paint-order:stroke fill markers" />
+	<circle cx="136.67" cy="106.76" r="23.876" :fill="themeVariables.fg" fill-opacity="0.5" stroke-dasharray="0.352425, 0.352425" stroke-width=".17621" style="paint-order:stroke fill markers" />
+	<g :fill="themeVariables.fg" fill-rule="evenodd" stroke-width=".26458">
+		<rect x="171.27" y="87.815" width="48.576" height="6.8747" ry="3.4373"/>
+		<rect x="171.27" y="105.09" width="48.576" height="6.875" ry="3.4375"/>
+		<rect x="171.27" y="121.28" width="48.576" height="6.875" ry="3.4375"/>
+		<rect x="171.27" y="137.47" width="48.576" height="6.875" ry="3.4375"/>
+	</g>
+	<path d="m65.498 40.892h137.7" :stroke="themeVariables.divider" stroke-width="0.75" />
+	<g transform="matrix(.60823 0 0 .60823 25.45 75.755)" fill="none" :stroke="themeVariables.accent" stroke-linecap="round" stroke-linejoin="round" stroke-width="2">
+		<path d="m0 0h24v24h-24z" fill="none" stroke="none" />
+		<path d="m5 12h-2l9-9 9 9h-2" />
+		<path d="m5 12v7a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2v-7" />
+		<path d="m9 21v-6a2 2 0 0 1 2-2h2a2 2 0 0 1 2 2v6" />
+	</g>
+	<g transform="matrix(.61621 0 0 .61621 25.354 117.92)" fill="none" :stroke="themeVariables.fg" stroke-linecap="round" stroke-linejoin="round" stroke-width="2">
+		<path d="m0 0h24v24h-24z" fill="none" stroke="none" />
+		<path d="m10 5a2 2 0 1 1 4 0 7 7 0 0 1 4 6v3a4 4 0 0 0 2 3h-16a4 4 0 0 0 2-3v-3a7 7 0 0 1 4-6" />
+		<path d="m9 17v1a3 3 0 0 0 6 0v-1" />
+	</g>
+	<image x="20.948" y="18.388" width="23.602" height="23.602" image-rendering="optimizeSpeed" preserveAspectRatio="xMidYMid meet" v-bind="{ 'xlink:href': instance.iconUrl || '/favicon.ico' }" />
+</svg>
+</template>
+
+<script setup lang="ts">
+import { ref, watch } from 'vue';
+import { instance } from '@/instance.js';
+import { compile } from '@/theme.js';
+import type { Theme } from '@/theme.js';
+import { deepClone } from '@/utility/clone.js';
+import lightTheme from '@@/themes/_light.json5';
+import darkTheme from '@@/themes/_dark.json5';
+
+const props = defineProps<{
+	theme: Theme;
+}>();
+
+const themeVariables = ref<{
+	bg: string;
+	acrylicBg: string;
+	panel: string;
+	fg: string;
+	divider: string;
+	accent: string;
+	accentedBg: string;
+}>({
+	bg: 'var(--MI_THEME-bg)',
+	acrylicBg: 'var(--MI_THEME-acrylicBg)',
+	panel: 'var(--MI_THEME-panel)',
+	fg: 'var(--MI_THEME-fg)',
+	divider: 'var(--MI_THEME-divider)',
+	accent: 'var(--MI_THEME-accent)',
+	accentedBg: 'var(--MI_THEME-accentedBg)',
+});
+
+watch(() => props.theme, (theme) => {
+	if (theme == null) return;
+
+	const _theme = deepClone(theme);
+
+	if (_theme?.base != null) {
+		const base = [lightTheme, darkTheme].find(x => x.id === _theme.base);
+		if (base) _theme.props = Object.assign({}, base.props, _theme.props);
+	}
+
+	const compiled = compile(_theme);
+
+	themeVariables.value = {
+		bg: compiled.bg ?? 'var(--MI_THEME-bg)',
+		acrylicBg: compiled.acrylicBg ?? 'var(--MI_THEME-acrylicBg)',
+		panel: compiled.panel ?? 'var(--MI_THEME-panel)',
+		fg: compiled.fg ?? 'var(--MI_THEME-fg)',
+		divider: compiled.divider ?? 'var(--MI_THEME-divider)',
+		accent: compiled.accent ?? 'var(--MI_THEME-accent)',
+		accentedBg: compiled.accentedBg ?? 'var(--MI_THEME-accentedBg)',
+	};
+}, { immediate: true });
+</script>
diff --git a/packages/frontend/src/pages/settings/theme.vue b/packages/frontend/src/pages/settings/theme.vue
index 71dba777b7..0e4f791f2c 100644
--- a/packages/frontend/src/pages/settings/theme.vue
+++ b/packages/frontend/src/pages/settings/theme.vue
@@ -5,7 +5,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 <template>
 <SearchMarker path="/settings/theme" :label="i18n.ts.theme" :keywords="['theme']" icon="ti ti-palette">
-	<div class="_gaps_m rsljpzjq">
+	<div class="_gaps_m">
 		<div v-adaptive-border class="rfqxtzch _panel">
 			<div class="toggle">
 				<div class="toggleWrapper">
@@ -36,23 +36,149 @@ SPDX-License-Identifier: AGPL-3.0-only
 			</div>
 		</div>
 
-		<div class="selects">
-			<div class="select">
+		<div class="_gaps">
+			<template v-if="!darkMode">
 				<SearchMarker :keywords="['light', 'theme']">
-					<MkSelect v-model="lightThemeId" large :items="lightThemeSelectorItems">
+					<MkFolder :defaultOpen="true" :max-height="500">
+						<template #icon><i class="ti ti-sun"></i></template>
 						<template #label><SearchLabel>{{ i18n.ts.themeForLightMode }}</SearchLabel></template>
-						<template #prefix><i class="ti ti-sun"></i></template>
-					</MkSelect>
+						<template #caption>{{ lightThemeName }}</template>
+
+						<div class="_gaps_m">
+							<FormSection v-if="instanceLightTheme != null" first>
+								<template #label>{{ i18n.ts._theme.instanceTheme }}</template>
+								<div :class="$style.themeSelect">
+									<div :class="$style.themeItemOuter">
+										<input
+											:id="`themeRadio_${instanceLightTheme.id}`"
+											v-model="lightThemeId"
+											type="radio"
+											name="lightTheme"
+											:class="$style.themeRadio"
+											:value="instanceLightTheme.id"
+										/>
+										<label :for="`themeRadio_${instanceLightTheme.id}`" :class="$style.themeItemRoot" class="_button">
+											<MkThemePreview :theme="instanceLightTheme" :class="$style.themeItemPreview"/>
+											<div :class="$style.themeItemCaption">{{ instanceLightTheme.name }}</div>
+										</label>
+									</div>
+								</div>
+							</FormSection>
+
+							<FormSection v-if="installedLightThemes.length > 0" :first="instanceLightTheme == null">
+								<template #label>{{ i18n.ts._theme.installedThemes }}</template>
+								<div :class="$style.themeSelect">
+									<div v-for="theme in installedLightThemes" :class="$style.themeItemOuter">
+										<input
+											:id="`themeRadio_${theme.id}`"
+											v-model="lightThemeId"
+											type="radio"
+											name="lightTheme"
+											:class="$style.themeRadio"
+											:value="theme.id"
+										/>
+										<label :for="`themeRadio_${theme.id}`" :class="$style.themeItemRoot" class="_button">
+											<MkThemePreview :theme="theme" :class="$style.themeItemPreview"/>
+											<div :class="$style.themeItemCaption">{{ theme.name }}</div>
+										</label>
+									</div>
+								</div>
+							</FormSection>
+
+							<FormSection :first="installedLightThemes.length === 0 && instanceLightTheme == null">
+								<template #label>{{ i18n.ts._theme.builtinThemes }}</template>
+								<div :class="$style.themeSelect">
+									<div v-for="theme in builtinLightThemes" :class="$style.themeItemOuter">
+										<input
+											:id="`themeRadio_${theme.id}`"
+											v-model="lightThemeId"
+											type="radio"
+											name="lightTheme"
+											:class="$style.themeRadio"
+											:value="theme.id"
+										/>
+										<label :for="`themeRadio_${theme.id}`" :class="$style.themeItemRoot" class="_button">
+											<MkThemePreview :theme="theme" :class="$style.themeItemPreview"/>
+											<div :class="$style.themeItemCaption">{{ theme.name }}</div>
+										</label>
+									</div>
+								</div>
+							</FormSection>
+						</div>
+					</MkFolder>
 				</SearchMarker>
-			</div>
-			<div class="select">
+			</template>
+			<template v-else>
 				<SearchMarker :keywords="['dark', 'theme']">
-					<MkSelect v-model="darkThemeId" large :items="darkThemeSelectorItems">
+					<MkFolder :defaultOpen="true" :max-height="500">
+						<template #icon><i class="ti ti-moon"></i></template>
 						<template #label><SearchLabel>{{ i18n.ts.themeForDarkMode }}</SearchLabel></template>
-						<template #prefix><i class="ti ti-moon"></i></template>
-					</MkSelect>
+						<template #caption>{{ darkThemeName }}</template>
+
+						<div class="_gaps_m">
+							<FormSection v-if="instanceDarkTheme != null" first>
+								<template #label>{{ i18n.ts._theme.instanceTheme }}</template>
+								<div :class="$style.themeSelect">
+									<div :class="$style.themeItemOuter">
+										<input
+											:id="`themeRadio_${instanceDarkTheme.id}`"
+											v-model="darkThemeId"
+											type="radio"
+											name="darkTheme"
+											:class="$style.themeRadio"
+											:value="instanceDarkTheme.id"
+										/>
+										<label :for="`themeRadio_${instanceDarkTheme.id}`" :class="$style.themeItemRoot" class="_button">
+											<MkThemePreview :theme="instanceDarkTheme" :class="$style.themeItemPreview"/>
+											<div :class="$style.themeItemCaption">{{ instanceDarkTheme.name }}</div>
+										</label>
+									</div>
+								</div>
+							</FormSection>
+
+							<FormSection v-if="installedDarkThemes.length > 0" :first="instanceDarkTheme == null">
+								<template #label>{{ i18n.ts._theme.installedThemes }}</template>
+								<div :class="$style.themeSelect">
+									<div v-for="theme in installedDarkThemes" :class="$style.themeItemOuter">
+										<input
+											:id="`themeRadio_${theme.id}`"
+											v-model="darkThemeId"
+											type="radio"
+											name="darkTheme"
+											:class="$style.themeRadio"
+											:value="theme.id"
+										/>
+										<label :for="`themeRadio_${theme.id}`" :class="$style.themeItemRoot" class="_button">
+											<MkThemePreview :theme="theme" :class="$style.themeItemPreview"/>
+											<div :class="$style.themeItemCaption">{{ theme.name }}</div>
+										</label>
+									</div>
+								</div>
+							</FormSection>
+
+							<FormSection :first="installedDarkThemes.length === 0 && instanceDarkTheme == null">
+								<template #label>{{ i18n.ts._theme.builtinThemes }}</template>
+								<div :class="$style.themeSelect">
+									<div v-for="theme in builtinDarkThemes" :class="$style.themeItemOuter">
+										<input
+											:id="`themeRadio_${theme.id}`"
+											v-model="darkThemeId"
+											type="radio"
+											name="darkTheme"
+											:class="$style.themeRadio"
+											:value="theme.id"
+										/>
+										<label :for="`themeRadio_${theme.id}`" :class="$style.themeItemRoot" class="_button">
+											<MkThemePreview :theme="theme" :class="$style.themeItemPreview"/>
+											<div :class="$style.themeItemCaption">{{ theme.name }}</div>
+										</label>
+									</div>
+								</div>
+							</FormSection>
+						</div>
+					</MkFolder>
 				</SearchMarker>
-			</div>
+			</template>
 		</div>
 
 		<FormSection>
@@ -77,12 +203,13 @@ import { computed, onActivated, ref, watch } from 'vue';
 import JSON5 from 'json5';
 import defaultLightTheme from '@@/themes/l-light.json5';
 import defaultDarkTheme from '@@/themes/d-green-lime.json5';
-import type { MkSelectItem } from '@/components/MkSelect.vue';
+import type { Theme } from '@/theme.js';
 import MkSwitch from '@/components/MkSwitch.vue';
-import MkSelect from '@/components/MkSelect.vue';
 import FormSection from '@/components/form/section.vue';
 import FormLink from '@/components/form/link.vue';
 import MkButton from '@/components/MkButton.vue';
+import MkFolder from '@/components/MkFolder.vue';
+import MkThemePreview from '@/components/MkThemePreview.vue';
 import { getBuiltinThemesRef } from '@/theme.js';
 import { selectFile } from '@/utility/select-file.js';
 import { isDeviceDarkmode } from '@/utility/is-device-darkmode.js';
@@ -99,79 +226,16 @@ import { prefer } from '@/preferences.js';
 const installedThemes = ref(getThemes());
 const builtinThemes = getBuiltinThemesRef();
 
-const instanceDarkTheme = computed(() => instance.defaultDarkTheme ? JSON5.parse(instance.defaultDarkTheme) : null);
+const instanceDarkTheme = computed<Theme | null>(() => instance.defaultDarkTheme ? JSON5.parse(instance.defaultDarkTheme) : null);
 const installedDarkThemes = computed(() => installedThemes.value.filter(t => t.base === 'dark' || t.kind === 'dark'));
 const builtinDarkThemes = computed(() => builtinThemes.value.filter(t => t.base === 'dark' || t.kind === 'dark'));
-const instanceLightTheme = computed(() => instance.defaultLightTheme ? JSON5.parse(instance.defaultLightTheme) : null);
+const instanceLightTheme = computed<Theme | null>(() => instance.defaultLightTheme ? JSON5.parse(instance.defaultLightTheme) : null);
 const installedLightThemes = computed(() => installedThemes.value.filter(t => t.base === 'light' || t.kind === 'light'));
 const builtinLightThemes = computed(() => builtinThemes.value.filter(t => t.base === 'light' || t.kind === 'light'));
 const themes = computed(() => uniqueBy([instanceDarkTheme.value, instanceLightTheme.value, ...builtinThemes.value, ...installedThemes.value].filter(x => x != null), theme => theme.id));
 
-const lightThemeSelectorItems = computed(() => {
-	const items = [] as MkSelectItem[];
-	if (instanceLightTheme.value) {
-		items.push({
-			type: 'option',
-			value: instanceLightTheme.value.id,
-			label: instanceLightTheme.value.name,
-		});
-	}
-	if (installedLightThemes.value.length > 0) {
-		items.push({
-			type: 'group',
-			label: i18n.ts._theme.installedThemes,
-			items: installedLightThemes.value.map(x => ({
-				type: 'option',
-				value: x.id,
-				label: x.name,
-			})),
-		});
-	}
-	items.push({
-		type: 'group',
-		label: i18n.ts._theme.builtinThemes,
-		items: builtinLightThemes.value.map(x => ({
-			type: 'option',
-			value: x.id,
-			label: x.name,
-		})),
-	});
-	return items;
-});
-
-const darkThemeSelectorItems = computed(() => {
-	const items = [] as MkSelectItem[];
-	if (instanceDarkTheme.value) {
-		items.push({
-			type: 'option',
-			value: instanceDarkTheme.value.id,
-			label: instanceDarkTheme.value.name,
-		});
-	}
-	if (installedDarkThemes.value.length > 0) {
-		items.push({
-			type: 'group',
-			label: i18n.ts._theme.installedThemes,
-			items: installedDarkThemes.value.map(x => ({
-				type: 'option',
-				value: x.id,
-				label: x.name,
-			})),
-		});
-	}
-	items.push({
-		type: 'group',
-		label: i18n.ts._theme.builtinThemes,
-		items: builtinDarkThemes.value.map(x => ({
-			type: 'option',
-			value: x.id,
-			label: x.name,
-		})),
-	});
-	return items;
-});
-
 const darkTheme = prefer.r.darkTheme;
+const darkThemeName = computed(() => darkTheme.value?.name ?? defaultDarkTheme.name);
 const darkThemeId = computed({
 	get() {
 		return darkTheme.value ? darkTheme.value.id : defaultDarkTheme.id;
@@ -184,6 +248,7 @@ const darkThemeId = computed({
 	},
 });
 const lightTheme = prefer.r.lightTheme;
+const lightThemeName = computed(() => lightTheme.value?.name ?? defaultLightTheme.name);
 const lightThemeId = computed({
 	get() {
 		return lightTheme.value ? lightTheme.value.id : defaultLightTheme.id;
@@ -236,6 +301,57 @@ definePage(() => ({
 }));
 </script>
 
+<style module>
+.themeSelect {
+	display: grid;
+	grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
+	gap: var(--MI-margin);
+}
+
+.themeItemOuter {
+	position: relative;
+}
+
+.themeRadio {
+	position: absolute;
+	clip: rect(0, 0, 0, 0);
+	pointer-events: none;
+}
+
+.themeItemRoot {
+	position: relative;
+	display: block;
+	overflow: clip;
+	box-sizing: border-box;
+	border: 2px solid var(--MI_THEME-divider);
+	border-radius: var(--MI-radius);
+}
+
+.themeRadio:focus-visible + .themeItemRoot {
+	outline: 2px solid var(--MI_THEME-focus);
+	outline-offset: 2px;
+}
+
+.themeRadio:checked + .themeItemRoot {
+	border-color: var(--MI_THEME-accent);
+}
+
+.themeItemPreview {
+	display: block;
+	width: calc(100% + 2px);
+	height: auto;
+	margin-left: -1px;
+	border-bottom: 1px solid var(--MI_THEME-divider);
+}
+
+.themeItemCaption {
+	box-sizing: border-box;
+	padding: 8px 12px;
+	text-align: center;
+	font-size: 80%;
+}
+</style>
+
 <style lang="scss" scoped>
 .rfqxtzch {
 	border-radius: 6px;
@@ -471,17 +587,4 @@ definePage(() => ({
 		border-top: solid 0.5px var(--MI_THEME-divider);
 	}
 }
-
-.rsljpzjq {
-	> .selects {
-		display: flex;
-		gap: 1.5em var(--MI-margin);
-		flex-wrap: wrap;
-
-		> .select {
-			flex: 1;
-			min-width: 280px;
-		}
-	}
-}
 </style>
diff --git a/packages/frontend/src/theme.ts b/packages/frontend/src/theme.ts
index ed2f1d3164..970d143b97 100644
--- a/packages/frontend/src/theme.ts
+++ b/packages/frontend/src/theme.ts
@@ -114,7 +114,7 @@ export function applyTheme(theme: Theme, persist = true) {
 	globalEvents.emit('themeChanging');
 }
 
-function compile(theme: Theme): Record<string, string> {
+export function compile(theme: Theme): Record<string, string> {
 	function getColor(val: string): tinycolor.Instance {
 		if (val[0] === '@') { // ref (prop)
 			return getColor(theme.props[val.substring(1)]);
diff --git a/packages/frontend/src/utility/autogen/settings-search-index.ts b/packages/frontend/src/utility/autogen/settings-search-index.ts
index 66476672e3..db4459bf06 100644
--- a/packages/frontend/src/utility/autogen/settings-search-index.ts
+++ b/packages/frontend/src/utility/autogen/settings-search-index.ts
@@ -33,12 +33,12 @@ export const searchIndexes: SearchIndexItem[] = [
 				keywords: ['light', 'theme'],
 			},
 			{
-				id: 'eLOwK5Ia2',
+				id: 'CsSVILKpX',
 				label: i18n.ts.themeForDarkMode,
 				keywords: ['dark', 'theme'],
 			},
 			{
-				id: 'ujvMfyzUr',
+				id: '8wcoRp76b',
 				label: i18n.ts.setWallpaper,
 				keywords: ['wallpaper'],
 			},