diff --git a/paper-datatable.html b/paper-datatable.html
index d1c8907..419956f 100644
--- a/paper-datatable.html
+++ b/paper-datatable.html
@@ -745,7 +745,7 @@
 						if(notify) this.fire('selection-changed', {deselected: [key]});
 					}else{
 						if(notify) this.fire('selection-changed', {deselected: [key]});
-						this.set('selectedKey', undefined);
+						this.set('selectedKey', null);
 					}
 				},
 				/**