diff --git a/packages/backend/src/server/api/endpoints/drive/folders/create.ts b/packages/backend/src/server/api/endpoints/drive/folders/create.ts
index d18199f19b..d7e5fead0e 100644
--- a/packages/backend/src/server/api/endpoints/drive/folders/create.ts
+++ b/packages/backend/src/server/api/endpoints/drive/folders/create.ts
@@ -43,7 +43,7 @@ export const meta = {
 export const paramDef = {
 	type: 'object',
 	properties: {
-		name: { type: 'string', default: 'Untitled', maxLength: 200 },
+		name: { type: 'string', default: 'Untitled', minLength: 1, maxLength: 200 },
 		parentId: { type: 'string', format: 'misskey:id', nullable: true },
 	},
 	required: [],
diff --git a/packages/backend/src/server/api/endpoints/drive/folders/update.ts b/packages/backend/src/server/api/endpoints/drive/folders/update.ts
index f8683132b2..8bac84fcca 100644
--- a/packages/backend/src/server/api/endpoints/drive/folders/update.ts
+++ b/packages/backend/src/server/api/endpoints/drive/folders/update.ts
@@ -49,7 +49,7 @@ export const paramDef = {
 	type: 'object',
 	properties: {
 		folderId: { type: 'string', format: 'misskey:id' },
-		name: { type: 'string', maxLength: 200 },
+		name: { type: 'string', minLength: 1, maxLength: 200 },
 		parentId: { type: 'string', format: 'misskey:id', nullable: true },
 	},
 	required: ['folderId'],