diff --git a/Algorithms/205. Isomorphic Strings/205. Isomorphic Strings.go b/Algorithms/205. Isomorphic Strings/205. Isomorphic Strings.go
new file mode 100644
index 00000000..0154ad08
--- /dev/null
+++ b/Algorithms/205. Isomorphic Strings/205. Isomorphic Strings.go	
@@ -0,0 +1,29 @@
+package leetcode
+
+func isIsomorphic(s string, t string) bool {
+	strList := []byte(t)
+	patternByte := []byte(s)
+	if (s == "" && t != "") || (len(patternByte) != len(strList)) {
+		return false
+	}
+
+	pMap := map[byte]byte{}
+	sMap := map[byte]byte{}
+	for index, b := range patternByte {
+		if _, ok := pMap[b]; !ok {
+			if _, ok = sMap[strList[index]]; !ok {
+				pMap[b] = strList[index]
+				sMap[strList[index]] = b
+			} else {
+				if sMap[strList[index]] != b {
+					return false
+				}
+			}
+		} else {
+			if pMap[b] != strList[index] {
+				return false
+			}
+		}
+	}
+	return true
+}
diff --git a/Algorithms/205. Isomorphic Strings/205. Isomorphic Strings_test.go b/Algorithms/205. Isomorphic Strings/205. Isomorphic Strings_test.go
new file mode 100644
index 00000000..a8913622
--- /dev/null
+++ b/Algorithms/205. Isomorphic Strings/205. Isomorphic Strings_test.go	
@@ -0,0 +1,58 @@
+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+type question205 struct {
+	para205
+	ans205
+}
+
+// para 是参数
+// one 代表第一个参数
+type para205 struct {
+	one string
+	two string
+}
+
+// ans 是答案
+// one 代表第一个答案
+type ans205 struct {
+	one bool
+}
+
+func Test_Problem205(t *testing.T) {
+
+	qs := []question205{
+
+		question205{
+			para205{"egg", "add"},
+			ans205{true},
+		},
+
+		question205{
+			para205{"foo", "bar"},
+			ans205{false},
+		},
+
+		question205{
+			para205{"paper", "title"},
+			ans205{true},
+		},
+
+		question205{
+			para205{"", ""},
+			ans205{true},
+		},
+	}
+
+	fmt.Printf("------------------------Leetcode Problem 205------------------------\n")
+
+	for _, q := range qs {
+		_, p := q.ans205, q.para205
+		fmt.Printf("【input】:%v       【output】:%v\n", p, isIsomorphic(p.one, p.two))
+	}
+	fmt.Printf("\n\n\n")
+}
diff --git a/Algorithms/205. Isomorphic Strings/README.md b/Algorithms/205. Isomorphic Strings/README.md
new file mode 100644
index 00000000..bcb5b464
--- /dev/null
+++ b/Algorithms/205. Isomorphic Strings/README.md	
@@ -0,0 +1,48 @@
+# [205. Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/)
+
+## 题目
+
+Given two strings s and t, determine if they are isomorphic.
+
+Two strings are isomorphic if the characters in s can be replaced to get t.
+
+All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character but a character may map to itself.
+
+Example 1:
+
+```c
+Input: s = "egg", t = "add"
+Output: true
+```
+
+Example 2:
+
+```c
+Input: s = "foo", t = "bar"
+Output: false
+```
+
+Example 3:
+
+```c
+Input: s = "paper", t = "title"
+Output: true
+```
+
+Note:   
+
+You may assume both s and t have the same length.
+
+
+
+
+## 题目大意
+
+这道题和第 290 题基本是一样的。第 290 题是模式匹配，这道题的题意是字符串映射，实质是一样的。
+
+给定一个初始字符串串，判断初始字符串是否可以通过字符映射的方式，映射到目标字符串，如果可以映射，则输出 true，反之输出 false。
+
+这道题做法和第 290 题基本一致。
+
+
+