diff --git a/src/Std/Lib/Markdown.php b/src/Std/Lib/Markdown.php
index 180de30..426f5e2 100644
--- a/src/Std/Lib/Markdown.php
+++ b/src/Std/Lib/Markdown.php
@@ -275,39 +275,39 @@ class Markdown {
 
     $patterns = [
       // 数式
-      '/\$\$([^$]+)\$\$/u' => function($matches): string {
+      '/(?<!\\\\)\$\$([^$]+)\$\$/u' => function($matches): string {
         $placeholder = "{{ALG".count($this->algebraicPlaceholder).'ALG}}';
         $this->algebraicPlaceholder[$placeholder] = $matches[1];
         return $placeholder;
       },
       // 太字
-      '/\*\*(.+?)\*\*/u' => '<strong>$1</strong>',
+      '/(?<!\\\\)\*\*(.+?)\*\*/u' => '<strong>$1</strong>',
       // 斜体
-      '/\*(.+?)\*/u' => '<em>$1</em>',
+      '/(?<!\\\\)\*(.+?)\*/u' => '<em>$1</em>',
       // 下線
-      '/\_(.+?)\_/u' => '<u>$1</u>',
+      '/(?<!\\\\)_(.+?)_/u' => '<u>$1</u>',
       // 取り消し線
-      '/\~(.+?)\~/u' => '<s>$1</s>',
+      '/(?<!\\\\)~(.+?)~/u' => '<s>$1</s>',
       // Blink (with speed)
-      '/!:\((.+?)\)(.+?):!/u' => '<span class="blink" style="animation-duration: $1s;">$2</span>',
+      '/(?<!\\\\)!:\((.+?)\)(.+?):!/u' => '<span class="blink" style="animation-duration: $1s;">$2</span>',
       // Blink
-      '/!:(.+?):!/u' => '<span class="blink">$1</span>',
+      '/(?<!\\\\)!:(.+?):!/u' => '<span class="blink">$1</span>',
       // フォントの大きさ
-      '/\^\((.+?)\)(.+?)\^/u' => '<span style="font-size: $1px;">$2</span>',
+      '/(?<!\\\\)\^\((.+?)\)(.+?)\^/u' => '<span style="font-size: $1px;">$2</span>',
       // フォントカラー
-      '/\%\((.+?)\)(.+?)\%/u' => '<span style="color: #$1;">$2</span>',
+      '/(?<!\\\\)\%\((.+?)\)(.+?)\%/u' => '<span style="color: #$1;">$2</span>',
       // 画像
-      '/\!\[(.*?)(?:#([^\]]*))?\]\((.+?)\)/u' => '<img style="width: 100%; $2" src="$3" alt="$1" />',
+      '/(?<!\\\\)\!\[(.*?)(?:#([^\]]*))?\]\((.+?)\)/u' => '<img style="width: 100%; $2" src="$3" alt="$1" />',
       // 音楽
-      '/\$\[([^\]]+)\]\(([^\)]+)\)/u' => '<audio controls><source src="$2" type="$1" /></audio>',
+      '/(?<!\\\\)\$\[([^\]]+)\]\(([^\)]+)\)/u' => '<audio controls><source src="$2" type="$1" /></audio>',
       // 動画
-      '/\#\[([^\]]+)\]\(([^\)]+)\)/u' => '<video style="max-width: 100%;" controls><source src="$2" type="$1" /></video>',
+      '/(?<!\\\\)\#\[([^\]]+)\]\(([^\)]+)\)/u' => '<video style="max-width: 100%;" controls><source src="$2" type="$1" /></video>',
       // リンク
-      '/\[(.+?)\]\((.+?)\)/u' => '<a href="$2">$1</a>',
+      '/(?<!\\\\)\[(.+?)\]\((.+?)\)/u' => '<a href="$2">$1</a>',
       // 振り仮名
-      '/\&lt;(.+?)\&gt;\((.+?)\)/u' => '<ruby>$1<rp>(</rp><rt>$2</rt><rp>)</rp></ruby>',
+      '/(?<!\\\\)&lt;(.+?)&gt;\((.+?)\)/u' => '<ruby>$1<rp>(</rp><rt>$2</rt><rp>)</rp></ruby>',
       // インラインコード
-      '/`(.+?)`/u' => '<code>$1</code>',
+      '/(?<!\\\\)`(.+?)`/u' => '<code>$1</code>',
     ];
 
     foreach ($patterns as $pattern => $replacement) {
@@ -325,6 +325,8 @@ class Markdown {
       $text = str_replace($placeholder, $this->parseAlgebraic($expr), $text);
     }
 
+    $text = preg_replace('/\\\\(.)/u', '$1', $text);
+
     return $text;
   }