diff --git a/LICENSE b/LICENSE
index 943b5f7..edc8984 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2021 LEE DONG GUN
+Copyright (c) 2021 - 2022 LEE DONG GUN
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index 9aa9e44..05556c4 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,22 @@
 # go-args-parser
-go args 파서 입니다.
+
+## Getting started
+
+### download
+
+```bash
+go get -v github.com/Sotaneum/go-args-parser
+```
+
+### API
+
+| name        | params              | returns             | example                                 | -                                                                                           |
+| ----------- | ------------------- | ------------------- | --------------------------------------- | ------------------------------------------------------------------------------------------- |
+| Args        | `map[string]string` | `map[string]string` | parser.Args(map[string]string{})        | Argument로 넘어오는 값을 `map[string]string` 포맷으로 반환합니다.                           |
+| EnvAll      | `map[string]string` | `map[string]string` | parser.EnvAll(map[string]string{})      | 모든 환경 변수 값을 `map[string]string` 포맷으로 반환합니다.                                |
+| Env         | `map[string]string` | `map[string]string` | parser.Env(map[string]string{})         | 환경 변수 값 중 `params`에 해당하는 key만 추출하여 `map[string]string` 포맷으로 반환합니다. |
+| ArgsJoinEnv | `map[string]string` | `map[string]string` | parser.ArgsJoinEnv(map[string]string{}) | `params`에 해당 하는 key만 추출하여 env로 부터 값을 가져오고 그 위에 Args를 덮어쓰기합니다. |
+
+## LICENSE
+
+[MIT](./LICENSE)
diff --git a/go.mod b/go.mod
index e80659b..795176f 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,3 @@
 module github.com/Sotaneum/go-args-parser
 
-go 1.17
+go 1.19
diff --git a/parser.go b/parser.go
index 5a92539..d9b37c7 100644
--- a/parser.go
+++ b/parser.go
@@ -18,9 +18,7 @@ func toKeyValue(data, pattern string) (string, string) {
 
 func Args(options map[string]string) map[string]string {
 	argsWithoutProg := os.Args[1:]
-
 	for _, arg := range argsWithoutProg {
-		println(arg)
 		key, value := toKeyValue(arg, "=")
 		if key == "" || value == "" {
 			continue
@@ -29,3 +27,30 @@ func Args(options map[string]string) map[string]string {
 	}
 	return options
 }
+
+func Env(options map[string]string) map[string]string{
+	for key, _ := range options {
+		value := os.Getenv(key)
+		if value == ""{
+			continue
+		}
+		options[key] = value
+	}
+	return options
+}
+
+func EnvAll(options map[string]string) map[string]string{
+	for _, item := range os.Environ() {
+		pair := strings.Split(item, "=")
+		options[pair[0]] = pair[1]
+	}
+	return options
+}
+
+func ArgsJoinEnv(options map[string]string) map[string]string{
+	return Args(Env(options))
+}
+
+func ArgsJoinEnvAll(options map[string]string) map[string]string{
+	return Args(EnvAll(options))
+}
\ No newline at end of file
diff --git a/parser_test.go b/parser_test.go
index 7f084f7..2ff30f4 100644
--- a/parser_test.go
+++ b/parser_test.go
@@ -9,4 +9,8 @@ import (
 
 func TestRunner(t *testing.T) {
 	fmt.Println(parser.Args(map[string]string{}))
+	fmt.Println(parser.EnvAll(map[string]string{}))
+	fmt.Println(parser.Env((map[string]string{"TMPDIR":"test"})))
+	fmt.Println(parser.ArgsJoinEnv((map[string]string{"TMPDIR":"test"})))
 }
+