diff --git a/src/expvar/expvar.go b/src/expvar/expvar.go
index 24c2d6b29a..1d51bc97f9 100644
--- a/src/expvar/expvar.go
+++ b/src/expvar/expvar.go
@@ -258,7 +258,8 @@ func Publish(name string, v Var) {
 	sort.Strings(varKeys)
 }
 
-// Get retrieves a named exported variable.
+// Get retrieves a named exported variable. It returns nil if the name has
+// not been registered.
 func Get(name string) Var {
 	mutex.RLock()
 	defer mutex.RUnlock()
diff --git a/src/expvar/expvar_test.go b/src/expvar/expvar_test.go
index 8bc633e4a9..385fea81ad 100644
--- a/src/expvar/expvar_test.go
+++ b/src/expvar/expvar_test.go
@@ -26,6 +26,14 @@ func RemoveAll() {
 	varKeys = nil
 }
 
+func TestNil(t *testing.T) {
+	RemoveAll()
+	val := Get("missing")
+	if val != nil {
+		t.Errorf("got %v, want nil", val)
+	}
+}
+
 func TestInt(t *testing.T) {
 	RemoveAll()
 	reqs := NewInt("requests")