diff --git a/CHANGELOG.md b/CHANGELOG.md
index 297f3a83..bec4dde5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 # intellij-markdown Changelog
 
 ## [Unreleased]
+- Generate HTML with `code-line line-added`/`line-deleted` classes for added/deleted lines in `diff` / `patch` blocks
 - Support tables inside list items
 - Android compatibility issues
 
diff --git a/src/commonMain/kotlin/org/intellij/markdown/html/GeneratingProviders.kt b/src/commonMain/kotlin/org/intellij/markdown/html/GeneratingProviders.kt
index eaabdc1c..4df462f0 100644
--- a/src/commonMain/kotlin/org/intellij/markdown/html/GeneratingProviders.kt
+++ b/src/commonMain/kotlin/org/intellij/markdown/html/GeneratingProviders.kt
@@ -197,18 +197,37 @@ internal class CodeFenceGeneratingProvider : GeneratingProvider {
         }
 
         var lastChildWasContent = false
+        var isDiff = false
 
         val attributes = ArrayList<String>()
         for (child in childrenToConsider) {
             if (state == 1 && child.type in listOf(MarkdownTokenTypes.CODE_FENCE_CONTENT,
                     MarkdownTokenTypes.EOL)) {
-                visitor.consumeHtml(HtmlGenerator.trimIndents(HtmlGenerator.leafText(text, child, false), indentBefore))
+                val content = HtmlGenerator.trimIndents(HtmlGenerator.leafText(text, child, false), indentBefore)
+                if (isDiff && child.type == MarkdownTokenTypes.CODE_FENCE_CONTENT) {
+                    val lineClass = when {
+                        content.startsWith("+") -> "line-added"
+                        content.startsWith("-") -> "line-deleted"
+                        else -> null
+                    }
+                    if (lineClass != null) {
+                        visitor.consumeTagOpen(child, "span", "class=\"code-line $lineClass\"")
+                        visitor.consumeHtml(content)
+                        visitor.consumeTagClose("span")
+                    } else {
+                        visitor.consumeHtml(content)
+                    }
+                } else {
+                    visitor.consumeHtml(content)
+                }
                 lastChildWasContent = child.type == MarkdownTokenTypes.CODE_FENCE_CONTENT
             }
             if (state == 0 && child.type == MarkdownTokenTypes.FENCE_LANG) {
-                attributes.add("class=\"language-${
-                HtmlGenerator.leafText(text, child).toString().trim().split(' ')[0]
-                }\"")
+                val info = HtmlGenerator.leafText(text, child).toString().trim()
+                val whitespaceIndex = info.indexOfFirst { it.isWhitespace() }
+                val language = if (whitespaceIndex == -1) info else info.substring(0, whitespaceIndex)
+                isDiff = language == "diff" || language == "patch"
+                attributes.add("class=\"language-$language\"")
             }
             if (state == 0 && child.type == MarkdownTokenTypes.EOL) {
                 visitor.consumeTagOpen(node, "code", *attributes.toTypedArray())
@@ -323,4 +342,3 @@ open class ImageGeneratingProvider(linkMap: LinkMap, baseURI: URI?) : LinkGenera
         val REGEX = Regex("[^a-zA-Z0-9 ]")
     }
 }
-
diff --git a/src/fileBasedTest/kotlin/org/intellij/markdown/HtmlGeneratorCommonTest.kt b/src/fileBasedTest/kotlin/org/intellij/markdown/HtmlGeneratorCommonTest.kt
index 2c349f9a..129fa790 100644
--- a/src/fileBasedTest/kotlin/org/intellij/markdown/HtmlGeneratorCommonTest.kt
+++ b/src/fileBasedTest/kotlin/org/intellij/markdown/HtmlGeneratorCommonTest.kt
@@ -50,6 +50,11 @@ class HtmlGeneratorCommonTest : HtmlGeneratorTestBase() {
         defaultTest()
     }
 
+    @Test
+    fun testDiffCodeFences() {
+        defaultTest()
+    }
+
     @Test
     fun testEscaping() {
         defaultTest()
diff --git a/src/fileBasedTest/resources/data/html/diffCodeFences.md b/src/fileBasedTest/resources/data/html/diffCodeFences.md
new file mode 100644
index 00000000..1ce86972
--- /dev/null
+++ b/src/fileBasedTest/resources/data/html/diffCodeFences.md
@@ -0,0 +1,32 @@
+```diff
++added line 1
++added line 2
++added line 3
+```
+
+```diff	metadata
++tab-separated info string
+```
+
+```diff
+-removed line 1
+-removed line 2
+-removed line 3
+```
+
+```diff
+ context line
++added line 1
++added line 2
+-removed line 1
+-removed line 2
+ context line
+```
+
+```diff
++ <tag>&
+-
++
+ plain line
+
+```
diff --git a/src/fileBasedTest/resources/data/html/diffCodeFences.txt b/src/fileBasedTest/resources/data/html/diffCodeFences.txt
new file mode 100644
index 00000000..2fd424a6
--- /dev/null
+++ b/src/fileBasedTest/resources/data/html/diffCodeFences.txt
@@ -0,0 +1,44 @@
+<body>
+<pre><code class="language-diff">
+<span class="code-line line-added">+added line 1</span>
+
+<span class="code-line line-added">+added line 2</span>
+
+<span class="code-line line-added">+added line 3</span>
+
+</code></pre>
+<pre><code class="language-diff">
+<span class="code-line line-added">+tab-separated info string</span>
+
+</code></pre>
+<pre><code class="language-diff">
+<span class="code-line line-deleted">-removed line 1</span>
+
+<span class="code-line line-deleted">-removed line 2</span>
+
+<span class="code-line line-deleted">-removed line 3</span>
+
+</code></pre>
+<pre><code class="language-diff">
+ context line
+<span class="code-line line-added">+added line 1</span>
+
+<span class="code-line line-added">+added line 2</span>
+
+<span class="code-line line-deleted">-removed line 1</span>
+
+<span class="code-line line-deleted">-removed line 2</span>
+
+ context line
+</code></pre>
+<pre><code class="language-diff">
+<span class="code-line line-added">+ &lt;tag&gt;&amp;</span>
+
+<span class="code-line line-deleted">-</span>
+
+<span class="code-line line-added">+</span>
+
+ plain line
+
+</code></pre>
+</body>