diff --git a/plugins/IntentionPowerPak/src/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassIntention.java b/plugins/IntentionPowerPak/src/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassIntention.java
index a806e9ba0e47..f3d69dee0c5a 100644
--- a/plugins/IntentionPowerPak/src/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassIntention.java
+++ b/plugins/IntentionPowerPak/src/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassIntention.java
@@ -106,7 +106,7 @@ public class ConvertInterfaceToClassIntention extends Intention {
     final PsiClass anInterface = (PsiClass)element.getParent();
     final SearchScope searchScope = anInterface.getUseScope();
     final Query<PsiClass> query = ClassInheritorsSearch.search(anInterface, searchScope, false);
-    final MultiMap<PsiElement, String> conflicts = new MultiMap();
+    final MultiMap<PsiElement, String> conflicts = new MultiMap<PsiElement, String>();
     query.forEach(new Processor<PsiClass>() {
       @Override
       public boolean process(PsiClass aClass) {
@@ -180,11 +180,14 @@ public class ConvertInterfaceToClassIntention extends Intention {
     final PsiReferenceList extendsList = anInterface.getExtendsList();
     final PsiReferenceList implementsList = anInterface.getImplementsList();
     assert extendsList != null;
-    final PsiJavaCodeReferenceElement[] referenceElements = extendsList.getReferenceElements();
-    for (PsiJavaCodeReferenceElement referenceElement : referenceElements) {
+    final PsiJavaCodeReferenceElement[] extendsRefElements = extendsList.getReferenceElements();
+    for (PsiJavaCodeReferenceElement referenceElement : extendsRefElements) {
       assert implementsList != null;
-      implementsList.add(referenceElement);
-      referenceElement.delete();
+      final PsiElement resolved = referenceElement.resolve();
+      if (resolved instanceof PsiClass && ((PsiClass)resolved).isInterface()) {
+        implementsList.add(referenceElement);
+        referenceElement.delete();
+      }
     }
   }
 
diff --git a/plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/InterfaceExtendsClass.java b/plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/InterfaceExtendsClass.java
new file mode 100644
index 000000000000..121a30d83524
--- /dev/null
+++ b/plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/InterfaceExtendsClass.java
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2000-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+abstract class Foo {
+
+}
+
+interface Bar extends F<caret>oo {
+
+}
+
diff --git a/plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/InterfaceExtendsClass_after.java b/plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/InterfaceExtendsClass_after.java
new file mode 100644
index 000000000000..2b708b2d7a67
--- /dev/null
+++ b/plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/InterfaceExtendsClass_after.java
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2000-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+abstract class Foo {
+
+}
+
+abstract class Bar extends Foo {
+
+}
+
diff --git a/plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassTest.java b/plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassTest.java
index c74f136872cb..b33a66c8fa4c 100644
--- a/plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassTest.java
+++ b/plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassTest.java
@@ -24,6 +24,7 @@ public class ConvertInterfaceToClassTest extends IPPTestCase {
   public void testExtensionMethods() { doTest(); }
   public void testInnerInterface() { doTest(); }
   public void testStaticMethods() { doTest(); }
+  public void testInterfaceExtendsClass() { doTest(); }
   public void testFunctionalExpressions() {
     try {
       doTest();