diff --git a/maven-model-builder/src/main/java/org/apache/maven/model/interpolation/StringVisitorModelInterpolator.java b/maven-model-builder/src/main/java/org/apache/maven/model/interpolation/StringVisitorModelInterpolator.java
index 02c7c889c5d5..32646304f6d5 100644
--- a/maven-model-builder/src/main/java/org/apache/maven/model/interpolation/StringVisitorModelInterpolator.java
+++ b/maven-model-builder/src/main/java/org/apache/maven/model/interpolation/StringVisitorModelInterpolator.java
@@ -1424,7 +1424,7 @@ private void visit( Properties properties )
                     {
                         String value = (String) v;
                         String inter = interpolate( value );
-                        if ( value != inter )
+                        if ( value != inter && inter != null )
                         {
                             entry.setValue( inter );
                         }