diff --git a/src/Methods/Personal/LockAccount.php b/src/Methods/Personal/LockAccount.php
new file mode 100644
index 0000000..0d8a44e
--- /dev/null
+++ b/src/Methods/Personal/LockAccount.php
@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * This file is part of web3.php package.
+ * 
+ * (c) Kuan-Cheng,Lai <alk03073135@gmail.com>
+ * 
+ * @author Peter Lai <alk03073135@gmail.com>
+ * @license MIT
+ */
+
+namespace Web3\Methods\Personal;
+
+use InvalidArgumentException;
+use Web3\Methods\EthMethod;
+use Web3\Validators\AddressValidator;
+use Web3\Validators\StringValidator;
+use Web3\Validators\QuantityValidator;
+use Web3\Formatters\AddressFormatter;
+use Web3\Formatters\StringFormatter;
+use Web3\Formatters\NumberFormatter;
+
+class LockAccount extends EthMethod
+{
+    /**
+     * validators
+     * 
+     * @var array
+     */
+    protected $validators = [
+        AddressValidator::class
+    ];
+
+    /**
+     * inputFormatters
+     * 
+     * @var array
+     */
+    protected $inputFormatters = [
+        AddressFormatter::class
+    ];
+
+    /**
+     * outputFormatters
+     * 
+     * @var array
+     */
+    protected $outputFormatters = [];
+
+    /**
+     * defaultValues
+     * 
+     * @var array
+     */
+    protected $defaultValues = [];
+
+    /**
+     * construct
+     * 
+     * @param string $method
+     * @param array $arguments
+     * @return void
+     */
+    // public function __construct($method='', $arguments=[])
+    // {
+    //     parent::__construct($method, $arguments);
+    // }
+}
+
diff --git a/src/Personal.php b/src/Personal.php
index 77c5e4c..75aa200 100644
--- a/src/Personal.php
+++ b/src/Personal.php
@@ -38,7 +38,7 @@ class Personal
      * @var array
      */
     private $allowedMethods = [
-        'personal_listAccounts', 'personal_newAccount', 'personal_unlockAccount', 'personal_sendTransaction'
+        'personal_listAccounts', 'personal_newAccount', 'personal_unlockAccount', 'personal_lockAccount', 'personal_sendTransaction'
     ];
 
     /**
@@ -177,4 +177,4 @@ class Personal
 
         $this->provider->batch($status);
     }
-}
\ No newline at end of file
+}