diff --git a/library/src/commonMain/kotlin/dev/usbharu/markdown/Lexer.kt b/library/src/commonMain/kotlin/dev/usbharu/markdown/Lexer.kt
index dc6ad55..622fc3f 100644
--- a/library/src/commonMain/kotlin/dev/usbharu/markdown/Lexer.kt
+++ b/library/src/commonMain/kotlin/dev/usbharu/markdown/Lexer.kt
@@ -68,6 +68,20 @@ class Lexer {
                             }
                         }
 
+                        next == '~' || next == '～' -> {
+                            if (iterator.peekOrNull() == next) {
+                                iterator.next()
+                                val peekString = peekString(iterator, next, next)
+                                if (peekString == null) {
+                                    addText(tokens, "$next$next")
+                                } else {
+                                    tokens.add(Strike(peekString))
+                                    iterator.skip(peekString.length + 2)
+                                }
+                            } else {
+                                addText(tokens, next.toString())
+                            }
+                        }
 
                         else -> {
                             addText(tokens, next.toString())
@@ -88,7 +102,6 @@ class Lexer {
             inQuote = false
         }
 
-        println(tokens)
         val lastToken = tokens.lastOrNull()
         if (lastToken is Break) {
             if (lastToken.count == 1) {
@@ -161,7 +174,7 @@ class Lexer {
             }
 
         } else {
-            val peekString = peekString(next, iterator)
+            val peekString = peekString(iterator, next)
             if (peekString != null && peekString.isEmpty()) {
                 addText(tokens, "$next$next")
                 iterator.next()
@@ -345,17 +358,24 @@ class Lexer {
         return count
     }
 
-    fun peekString(char: Char, iterator: PeekableCharIterator): String? {
+    fun peekString(iterator: PeekableCharIterator, vararg char: Char): String? {
         var counter = 0
         val stringBuilder = StringBuilder()
-        while (iterator.peekOrNull(counter) != null && iterator.peekOrNull(counter) != char) {
+        var checkCounter = 0
+        while (iterator.peekOrNull(counter) != null && checkCounter < char.size) {
             stringBuilder.append(iterator.peekOrNull(counter))
+            if (iterator.peekOrNull(counter) == char[checkCounter]) {
+                checkCounter++
+            } else {
+                checkCounter = 0
+            }
             counter++
         }
-        if (iterator.peekOrNull(counter) == null) {
+        if (iterator.peekOrNull(counter) == null && checkCounter != char.size) {
             return null
         }
-        return stringBuilder.toString()
+        val string = stringBuilder.toString()
+        return string.substring(0, string.length - char.size)
     }
 
     fun collect(iterator: PeekableCharIterator): String {
diff --git a/library/src/commonMain/kotlin/dev/usbharu/markdown/Token.kt b/library/src/commonMain/kotlin/dev/usbharu/markdown/Token.kt
index 5540861..5a45610 100644
--- a/library/src/commonMain/kotlin/dev/usbharu/markdown/Token.kt
+++ b/library/src/commonMain/kotlin/dev/usbharu/markdown/Token.kt
@@ -29,4 +29,4 @@ data class UrlTitle(val title: String) : Token()
 data class InlineCodeBlock(val text: String) : Token()
 data class CodeBlock(val text: String) : Token()
 data class CodeBlockLanguage(val language: String, val filename: String) : Token()
-data object Tilde : Token()
\ No newline at end of file
+data class Strike(val strike: String) : Token()
\ No newline at end of file
diff --git a/library/src/commonTest/kotlin/dev/usbharu/markdown/LexerTest.kt b/library/src/commonTest/kotlin/dev/usbharu/markdown/LexerTest.kt
index 55330a0..fae9fc1 100644
--- a/library/src/commonTest/kotlin/dev/usbharu/markdown/LexerTest.kt
+++ b/library/src/commonTest/kotlin/dev/usbharu/markdown/LexerTest.kt
@@ -2,6 +2,7 @@ package dev.usbharu.markdown
 
 import kotlin.test.Test
 import kotlin.test.assertContentEquals
+import kotlin.test.assertEquals
 
 class LexerTest {
 
@@ -825,4 +826,63 @@ class LexerTest {
             ), actual
         )
     }
+
+    @Test
+    fun peekStringTest() {
+        val lexer = Lexer()
+        val iterator = PeekableCharIterator("*a**a***".toCharArray())
+        val peekString = lexer.peekString(iterator, '*', '*', '*')
+
+        println(peekString)
+
+        assertEquals("*a**a", peekString)
+    }
+
+    @Test
+    fun 打ち消し線() {
+        val lexer = Lexer()
+
+        val actual = lexer.lex("~~aiueo~~")
+
+        println(actual)
+
+        assertContentEquals(
+            listOf(
+                Strike("aiueo")
+            ), actual
+        )
+    }
+
+    @Test
+    fun 打ち消し線2() {
+        val lexer = Lexer()
+
+        val actual = lexer.lex("aiueo ~~aiueo~~bcde")
+
+        println(actual)
+
+        assertContentEquals(
+            listOf(
+                Text("aiueo"),
+                Whitespace(1, ' '),
+                Strike("aiueo"),
+                Text("bcde")
+            ), actual
+        )
+    }
+
+    @Test
+    fun 打ち消し線かと思ったら違った() {
+        val lexer = Lexer()
+
+        val actual = lexer.lex("aiueo~~abcd")
+
+        println(actual)
+
+        assertContentEquals(
+            listOf(
+                Text("aiueo~~abcd")
+            ), actual
+        )
+    }
 }
\ No newline at end of file