diff --git a/lib/mixins.less b/lib/mixins.less
index ca7893dafea0..35dd3ca015ee 100644
--- a/lib/mixins.less
+++ b/lib/mixins.less
@@ -100,6 +100,7 @@
 .border-radius(@radius: 5px) {
   -webkit-border-radius: @radius;
      -moz-border-radius: @radius;
+      -ms-border-radius: @radius;
           border-radius: @radius;
 }