diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index e9430a058f8..630d108c0e9 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -2945,7 +2945,7 @@ module ts {
                 let type = getApparentType(current);
                 if (type !== unknownType) {
                     let prop = getPropertyOfType(type, name);
-                    if (!prop) {
+                    if (!prop || getDeclarationFlagsFromSymbol(prop) & (NodeFlags.Private | NodeFlags.Protected)) {
                         return undefined;
                     }
                     if (!props) {