diff --git a/idea/src/org/jetbrains/jet/plugin/hierarchy/KotlinTypeHierarchyProvider.java b/idea/src/org/jetbrains/jet/plugin/hierarchy/KotlinTypeHierarchyProvider.java
index 307768c4efc..e4de5156af9 100644
--- a/idea/src/org/jetbrains/jet/plugin/hierarchy/KotlinTypeHierarchyProvider.java
+++ b/idea/src/org/jetbrains/jet/plugin/hierarchy/KotlinTypeHierarchyProvider.java
@@ -36,6 +36,7 @@ import org.jetbrains.jet.lang.psi.JetFile;
 import org.jetbrains.jet.lang.psi.JetNamedFunction;
 import org.jetbrains.jet.lang.resolve.BindingContext;
 import org.jetbrains.jet.lang.types.JetType;
+import org.jetbrains.jet.plugin.JetPluginUtil;
 import org.jetbrains.jet.plugin.caches.resolve.KotlinCacheManagerUtil;
 import org.jetbrains.jet.plugin.libraries.JetSourceNavigationHelper;
 import org.jetbrains.jet.plugin.stubindex.JetShortClassNameIndex;
@@ -55,6 +56,8 @@ public class KotlinTypeHierarchyProvider extends JavaTypeHierarchyProvider {
             PsiFile file = PsiDocumentManager.getInstance(project).getPsiFile(editor.getDocument());
             if (!(file instanceof JetFile)) return null;
 
+            if (!JetPluginUtil.isInSourceContent(file)) return null;
+
             PsiElement target = TargetElementUtilBase.findTargetElement(editor, TargetElementUtilBase.getInstance().getAllAccepted());
 
             if (target instanceof PsiClass) {