diff --git a/angular-tree-control.js b/angular-tree-control.js
index 38439ea..4b402b8 100644
--- a/angular-tree-control.js
+++ b/angular-tree-control.js
@@ -261,7 +261,7 @@ if (typeof module !== "undefined" && typeof exports !== "undefined" && module.ex
                     if(!template) {
                         template =
                             '<ul {{options.ulClass}} >' +
-                            '<li ng-repeat="node in node.{{options.nodeChildren}} | filter:filterExpression:filterComparator {{options.orderBy}}" ng-class="headClass(node)" {{options.liClass}}' +
+                            '<li ng-repeat="node in node.{{options.nodeChildren}} track by $index | filter:filterExpression:filterComparator {{options.orderBy}}" ng-class="headClass(node)" {{options.liClass}}' +
                             'set-node-to-data>' +
                             '<i class="tree-branch-head" ng-class="iBranchClass()" ng-click="selectNodeHead(node)"></i>' +
                             '<i class="tree-leaf-head {{options.iLeafClass}}"></i>' +