diff --git a/env_short_long_name.go b/env_short_long_name.go
index 5194606..35539c0 100644
--- a/env_short_long_name.go
+++ b/env_short_long_name.go
@@ -6,15 +6,29 @@ import "strings"
 // LongOpt -> short-opt
 // long_opt -> long-opt
 
+// 专有名字不转换
+// 专有名字词
+var specialNames = map[string]bool{
+	"JSON": true,
+	"XML":  true,
+	"YAML": true,
+	// Add more special names here
+}
+
 func wordStart(b byte) bool {
 
 	return b >= 'A' && b <= 'Z' || b == '_'
 }
 
+// gnuOptionName 转换为gnu风格的名字
 func gnuOptionName(opt string) (string, error) {
 
 	var name strings.Builder
 
+	if specialNames[opt] {
+		return opt, nil
+	}
+
 	for i, b := range []byte(opt) {
 
 		if wordStart(b) {
@@ -37,10 +51,14 @@ func gnuOptionName(opt string) (string, error) {
 	return name.String(), nil
 }
 
+// 环境变量名字是大写，下划线(蛇形)风格
 func envOptionName(opt string) (string, error) {
 
 	var name strings.Builder
 
+	if specialNames[opt] {
+		return opt, nil
+	}
 	for i, b := range []byte(opt) {
 
 		if wordStart(b) {
diff --git a/env_short_long_name_test.go b/env_short_long_name_test.go
index 62a84e0..c1b583f 100644
--- a/env_short_long_name_test.go
+++ b/env_short_long_name_test.go
@@ -18,6 +18,7 @@ func Test_ShortLongName(t *testing.T) {
 		{"almost_all", "almost-all"},
 		{"_almost_all", "almost-all"},
 		{"LongOpt_all", "long-opt-all"},
+		{"JSON", "JSON"},
 	} {
 		got, err := gnuOptionName(tcase.in)
 		assert.NoError(t, err)
@@ -32,6 +33,7 @@ func Test_EnvName(t *testing.T) {
 		{"almost_all", "ALMOST_ALL"},
 		{"_almost_all", "ALMOST_ALL"},
 		{"envOpt_all", "ENV_OPT_ALL"},
+		{"JSON", "JSON"},
 	} {
 		got, err := envOptionName(tcase.in)
 		assert.NoError(t, err)