diff --git a/staging/src/k8s.io/kubectl/pkg/cmd/diff/diff_test.go b/staging/src/k8s.io/kubectl/pkg/cmd/diff/diff_test.go
index 434415ecf49..9c68fb38775 100644
--- a/staging/src/k8s.io/kubectl/pkg/cmd/diff/diff_test.go
+++ b/staging/src/k8s.io/kubectl/pkg/cmd/diff/diff_test.go
@@ -54,6 +54,11 @@ func (f *FakeObject) Live() runtime.Object {
 func TestDiffProgram(t *testing.T) {
 	externalDiffCommands := [3]string{"diff", "diff -ruN", "diff --report-identical-files"}
 
+	if oriLang := os.Getenv("LANG"); oriLang != "C" {
+		os.Setenv("LANG", "C")
+		defer os.Setenv("LANG", oriLang)
+	}
+
 	for i, c := range externalDiffCommands {
 		os.Setenv("KUBECTL_EXTERNAL_DIFF", c)
 		streams, _, stdout, _ := genericclioptions.NewTestIOStreams()