diff --git a/Python/Longest_Uncommon_Subsequence.py b/Python/Longest_Uncommon_Subsequence.py
new file mode 100644
index 0000000..8943408
--- /dev/null
+++ b/Python/Longest_Uncommon_Subsequence.py
@@ -0,0 +1,18 @@
+#Link Of Question :https://leetcode.com/problems/longest-uncommon-subsequence-i/
+#134.  Longest Uncommon Subsequence I 
+#Given two strings a and b, return the length of the longest uncommon subsequence between a and b. If the longest uncommon subsequence does not exist, return -1
+#Solution :
+
+class Solution:
+    def findLUSlength(self, a: str, b: str) -> int:
+        if a!=b:
+            return max(len(a),len(b))
+        return -1
+
+
+
+#Sample Input 1 : a = "aaa", b = "bbb"
+#Sample output 1 : 3
+
+#Sample input 2 : a = "aaa", b = "aaa"
+#Sample output 1 : -1  
\ No newline at end of file
diff --git a/Python/README.md b/Python/README.md
index 2c30bfb..4b55b53 100644
--- a/Python/README.md
+++ b/Python/README.md
@@ -6,3 +6,4 @@
 2 : Missing Number<br>
 3 : Peak Element <br>
 7 : Reverse Integer<br>
+521 : Longest Uncommon Subsequence I<br>