diff --git a/gin_test.go b/gin_test.go
index e641297c..f7df5aa8 100644
--- a/gin_test.go
+++ b/gin_test.go
@@ -678,13 +678,21 @@ func TestEngineValidateHeader(t *testing.T) {
 	}
 
 	{
-		// illegal header
+		// normal header with illegal element
 		header := "123.123.123.123, 30.30.30.30, 256.255.255.255"
 		ip, ok := e.validateHeader(header)
 		assert.False(t, ok)
 		assert.Empty(t, ip)
 	}
 
+	{
+		// illegal header
+		header := "foo/bar"
+		ip, ok := e.validateHeader(header)
+		assert.False(t, ok)
+		assert.Empty(t, ip)
+	}
+
 	{
 		// empty header
 		header := ""