diff --git a/CHANGELOG.md b/CHANGELOG.md
index 11999e48..defc3806 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@ Changelog
 =========
 
 * Add `forceescape` filter. Fixes [#782](https://github.com/mozilla/nunjucks/issues/782)
+* Fix "Invalid type: Is" error for `{% if value is defined %}. Fixes
+  [#1110](https://github.com/mozilla/nunjucks/issues/1110)
 
 3.1.2 (Feb 23 2018)
 -------------------
diff --git a/nunjucks/src/compiler.js b/nunjucks/src/compiler.js
index 03a3bc1d..6c000fe7 100644
--- a/nunjucks/src/compiler.js
+++ b/nunjucks/src/compiler.js
@@ -166,6 +166,7 @@ class Compiler extends Obj {
       nodes.Compare,
       nodes.InlineIf,
       nodes.In,
+      nodes.Is,
       nodes.And,
       nodes.Or,
       nodes.Not,