diff --git a/src/ol/layer/layergroup.js b/src/ol/layer/layergroup.js
index 4e00e74c5d..89fb0b5256 100644
--- a/src/ol/layer/layergroup.js
+++ b/src/ol/layer/layergroup.js
@@ -142,11 +142,11 @@ ol.layer.Group.prototype.handleLayersRemove_ = function(collectionEvent) {
 
 
 /**
- * @return {ol.Collection} Collection of layers.
+ * @return {ol.Collection|undefined} Collection of layers.
  * @todo stability experimental
  */
 ol.layer.Group.prototype.getLayers = function() {
-  return /** @type {ol.Collection} */ (this.get(
+  return /** @type {ol.Collection|undefined} */ (this.get(
       ol.layer.GroupProperty.LAYERS));
 };
 goog.exportProperty(
@@ -156,7 +156,7 @@ goog.exportProperty(
 
 
 /**
- * @param {ol.Collection} layers Collection of layers.
+ * @param {ol.Collection|undefined} layers Collection of layers.
  * @todo stability experimental
  */
 ol.layer.Group.prototype.setLayers = function(layers) {
diff --git a/src/ol/map.js b/src/ol/map.js
index 722ddc5ef6..a455b20d05 100644
--- a/src/ol/map.js
+++ b/src/ol/map.js
@@ -621,11 +621,16 @@ goog.exportProperty(
 
 /**
  * Get the collection of layers associated with this map.
- * @return {ol.Collection} Layers.
+ * @return {ol.Collection|undefined} Layers.
  * @todo stability experimental
  */
 ol.Map.prototype.getLayers = function() {
-  return this.getLayerGroup().getLayers();
+  var layerGroup = this.getLayerGroup();
+  if (goog.isDef(layerGroup)) {
+    return layerGroup.getLayers();
+  } else {
+    return undefined;
+  }
 };