diff --git a/problems/0242.有效的字母异位词.md b/problems/0242.有效的字母异位词.md
index 1b6b3109..3416ac06 100644
--- a/problems/0242.有效的字母异位词.md
+++ b/problems/0242.有效的字母异位词.md
@@ -221,6 +221,41 @@ func isAnagram(_ s: String, _ t: String) -> Bool {
 }
 ```
 
+PHP：
+```php
+class Solution {
+    /**
+     * @param String $s
+     * @param String $t
+     * @return Boolean
+     */
+    function isAnagram($s, $t) {
+        if (strlen($s) != strlen($t)) {
+            return false;
+        }
+        $table = [];
+        for ($i = 0; $i < strlen($s); $i++) {
+            if (!isset($table[$s[$i]])) {
+                $table[$s[$i]] = 1;
+            } else {
+                $table[$s[$i]]++;
+            }
+            if (!isset($table[$t[$i]])) {
+                $table[$t[$i]] = -1;
+            } else {
+                $table[$t[$i]]--;
+            }
+        }
+        foreach ($table as $record) {
+            if ($record != 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+}
+```
+
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