diff --git a/platform/diff-impl/src/com/intellij/diff/util/DiffUtil.java b/platform/diff-impl/src/com/intellij/diff/util/DiffUtil.java
index 602fb3a6b1d1..f8593a35ef78 100644
--- a/platform/diff-impl/src/com/intellij/diff/util/DiffUtil.java
+++ b/platform/diff-impl/src/com/intellij/diff/util/DiffUtil.java
@@ -51,6 +51,7 @@ import com.intellij.openapi.editor.highlighter.EditorHighlighter;
 import com.intellij.openapi.editor.highlighter.EditorHighlighterFactory;
 import com.intellij.openapi.editor.markup.TextAttributes;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
+import com.intellij.openapi.fileEditor.impl.text.TextEditorImpl;
 import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.fileTypes.PlainTextFileType;
 import com.intellij.openapi.fileTypes.SyntaxHighlighter;
@@ -190,6 +191,11 @@ public class DiffUtil {
       editor.getSettings().setTabSize(indentOptions.TAB_SIZE);
       editor.getSettings().setUseTabCharacter(indentOptions.USE_TAB_CHARACTER);
     }
+
+    Language language = content != null ? content.getUserData(DiffUserDataKeys.LANGUAGE) : null;
+    if (language == null) language = TextEditorImpl.getDocumentLanguage(editor);
+    editor.getSettings().setLanguage(language);
+
     editor.getSettings().setCaretRowShown(false);
     editor.reinitSettings();
   }