diff --git a/src/browser/ui/ReactDOMComponent.js b/src/browser/ui/ReactDOMComponent.js
index 74e55363e2..6b65664e86 100644
--- a/src/browser/ui/ReactDOMComponent.js
+++ b/src/browser/ui/ReactDOMComponent.js
@@ -212,7 +212,7 @@ ReactDOMComponent.Mixin = {
       // we can do a cheap identity compare here to determine if this is a
       // superfluous reconcile. It's possible for state to be mutable but such
       // change should trigger an update of the owner which would recreate
-      // the descriptor. We explicitly check for the existance of an owner since
+      // the descriptor. We explicitly check for the existence of an owner since
       // it's possible for a descriptor created outside a composite to be
       // deeply mutated and reused.
       return;
diff --git a/src/core/ReactCompositeComponent.js b/src/core/ReactCompositeComponent.js
index b7f9bd8b94..6f07a4b366 100644
--- a/src/core/ReactCompositeComponent.js
+++ b/src/core/ReactCompositeComponent.js
@@ -1073,7 +1073,7 @@ var ReactCompositeComponentMixin = {
       // we can do a cheap identity compare here to determine if this is a
       // superfluous reconcile. It's possible for state to be mutable but such
       // change should trigger an update of the owner which would recreate
-      // the descriptor. We explicitly check for the existance of an owner since
+      // the descriptor. We explicitly check for the existence of an owner since
       // it's possible for a descriptor created outside a composite to be
       // deeply mutated and reused.
       return;