diff --git a/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README.md b/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README.md
index 7ffe5b4fedb04..b4ea8613be039 100644
--- a/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README.md	
+++ b/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README.md	
@@ -189,6 +189,27 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param Integer[] $prices
+     * @return Integer
+     */
+    function maxProfit($prices) {
+        $win = 0;
+        $minPrice = $prices[0];
+        $len = count($prices);
+        for ($i = 1; $i < $len; $i++) {
+            $minPrice = min($minPrice, $prices[$i]);
+            $win = max($win, $prices[$i] - $minPrice);
+        }
+        return $win;
+    }
+}
+```
+
 ### **...**
 
 ```
diff --git a/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README_EN.md b/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README_EN.md
index 83abc35b5b499..ec0a4dee24c99 100644
--- a/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README_EN.md	
+++ b/solution/0100-0199/0121.Best Time to Buy and Sell Stock/README_EN.md	
@@ -173,6 +173,27 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param Integer[] $prices
+     * @return Integer
+     */
+    function maxProfit($prices) {
+        $win = 0;
+        $minPrice = $prices[0];
+        $len = count($prices);
+        for ($i = 1; $i < $len; $i++) {
+            $minPrice = min($minPrice, $prices[$i]);
+            $win = max($win, $prices[$i] - $minPrice);
+        }
+        return $win;
+    }
+}
+```
+
 ### **...**
 
 ```
diff --git a/solution/0100-0199/0121.Best Time to Buy and Sell Stock/Solution.php b/solution/0100-0199/0121.Best Time to Buy and Sell Stock/Solution.php
new file mode 100644
index 0000000000000..9f0d8961724a7
--- /dev/null
+++ b/solution/0100-0199/0121.Best Time to Buy and Sell Stock/Solution.php	
@@ -0,0 +1,16 @@
+class Solution {
+    /**
+     * @param Integer[] $prices
+     * @return Integer
+     */
+    function maxProfit($prices) {
+        $win = 0;
+        $minPrice = $prices[0];
+        $len = count($prices);
+        for ($i = 1; $i < $len; $i++) {
+            $minPrice = min($minPrice, $prices[$i]);
+            $win = max($win, $prices[$i] - $minPrice);
+        }
+        return $win;
+    }
+}
\ No newline at end of file