diff --git a/init.js b/init.js
index fd27011..3ce901b 100644
--- a/init.js
+++ b/init.js
@@ -25,6 +25,10 @@ module.exports = function init (modules) {
   }
 
   return function renderToString (vnode) {
+    if (typeof vnode === 'undefined' || vnode === null) {
+      return ''
+    }
+
     if (!vnode.sel && vnode.text) {
       return vnode.text
     }
diff --git a/test/index.js b/test/index.js
index d6f04b7..316bbd4 100644
--- a/test/index.js
+++ b/test/index.js
@@ -37,6 +37,12 @@ test('No modules', function (t) {
   ])
   t.equal(renderToString(vnode), '<div><p>Paragraph 1</p><p><img></p><ul><li>1</li><li>2</li><li>3</li></ul></div>', 'nesting')
 
+  vnode = h('div', [
+    undefined,
+    null
+  ])
+  t.equal(renderToString(vnode), '<div></div>', 'null / undefined')
+
   vnode = h('!', 'comment text')
   t.equal(renderToString(vnode), '<!--comment text-->', 'comment')