diff --git a/src/renderers/testing/ReactTestMount.js b/src/renderers/testing/ReactTestMount.js
index a58acb15af332..d964a1390a65f 100644
--- a/src/renderers/testing/ReactTestMount.js
+++ b/src/renderers/testing/ReactTestMount.js
@@ -122,6 +122,9 @@ ReactTestInstance.prototype.unmount = function(nextElement) {
 };
 ReactTestInstance.prototype.toJSON = function() {
   var inst = getHostComponentFromComposite(this._component);
+  if (inst === null) {
+    return null;
+  }
   return inst.toJSON();
 };
 
diff --git a/src/renderers/testing/__tests__/ReactTestRenderer-test.js b/src/renderers/testing/__tests__/ReactTestRenderer-test.js
index a20d442686d3b..24fff957ddc46 100644
--- a/src/renderers/testing/__tests__/ReactTestRenderer-test.js
+++ b/src/renderers/testing/__tests__/ReactTestRenderer-test.js
@@ -28,6 +28,14 @@ describe('ReactTestRenderer', function() {
     });
   });
 
+  it('renders a top-level empty component', function() {
+    function Empty() {
+      return null;
+    }
+    var renderer = ReactTestRenderer.create(<Empty />);
+    expect(renderer.toJSON()).toEqual(null);
+  });
+
   it('exposes a type flag', function() {
     function Link() {
       return <a role="link" />;