diff --git a/java/java-psi-api/src/com/intellij/psi/util/TypeConversionUtil.java b/java/java-psi-api/src/com/intellij/psi/util/TypeConversionUtil.java
index 0d4157481cc5..39d9e684ca08 100644
--- a/java/java-psi-api/src/com/intellij/psi/util/TypeConversionUtil.java
+++ b/java/java-psi-api/src/com/intellij/psi/util/TypeConversionUtil.java
@@ -202,6 +202,7 @@ public class TypeConversionUtil {
 
     if (isAssignable(fromType, toType)) return true;
 
+    if (!(fromType instanceof PsiClassType) || !(toType instanceof PsiClassType)) return false;
     PsiClassType fromClassType = (PsiClassType)fromType;
     PsiClassType toClassType = (PsiClassType)toType;