diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/PDOMIndexerJob.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/PDOMIndexerJob.java
index 48a151fa0b5..c550d8b36bd 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/PDOMIndexerJob.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/PDOMIndexerJob.java
@@ -172,6 +172,7 @@ public class PDOMIndexerJob extends Job {
 			synchronized(this) {
 				fMonitor= null;
 			}
+			monitorJob.cancel();
 			monitor.done();
 		}
 	}