diff --git a/src/loaders/BufferGeometryLoader.js b/src/loaders/BufferGeometryLoader.js
index b458ee9e37be59e2e4410dfa100a2313348533c7..d5653fbdb7445c903719b29fffb8e08e70815056 100644
--- a/src/loaders/BufferGeometryLoader.js
+++ b/src/loaders/BufferGeometryLoader.js
@@ -64,7 +64,7 @@ THREE.BufferGeometryLoader.prototype = {
 
 				var group = groups[ i ];
 
-				geometry.addGroup( group.start, group.count );
+				geometry.addGroup( group.start, group.count, group.materialIndex );
 
 			}