diff --git a/fetch.js b/fetch.js
index 06e4d1dc..018bbb36 100644
--- a/fetch.js
+++ b/fetch.js
@@ -44,7 +44,7 @@ function normalizeName(name) {
   if (typeof name !== 'string') {
     name = String(name)
   }
-  if (/[^a-z0-9\-#$%&'*+.^_`|~]/i.test(name)) {
+  if (/[^a-z0-9\-#$%&'*+.^_`|~]/i.test(name) || name === '') {
     throw new TypeError('Invalid character in header field name')
   }
   return name.toLowerCase()
diff --git a/test/test.js b/test/test.js
index a09ac4ad..1bebef88 100644
--- a/test/test.js
+++ b/test/test.js
@@ -262,6 +262,9 @@ exercise.forEach(function(exerciseMode) {
           var headers = new Headers()
           headers.set({field: 'value'}, 'application/json')
         }, TypeError)
+        assert.throws(function() {
+          new Headers({'': 'application/json'})
+        }, TypeError)
       })
       featureDependent(test, !brokenFF, 'is iterable with forEach', function() {
         var headers = new Headers()