diff --git a/src/Utils.php b/src/Utils.php
index d623b58..59c26de 100644
--- a/src/Utils.php
+++ b/src/Utils.php
@@ -136,6 +136,26 @@ class Utils
         return $value;
     }
 
+    /**
+     * isAddress
+     * To do: check address checksum
+     * 
+     * @param string
+     * @return bool
+     */
+    public static function isAddress($value)
+    {
+        if (!is_string($value)) {
+            throw new InvalidArgumentException('The value to isAddress function must be string.');
+        }
+        if (preg_match('/^(0x|0X)?[a-fA-F0-9]{40}$/', $value) == 1) {
+            return true;
+        } else {
+            // validate address checksum
+        }
+        return false;
+    }
+
     /**
      * sha3
      * keccak256
diff --git a/test/unit/UtilsTest.php b/test/unit/UtilsTest.php
index 529884d..a464cc0 100644
--- a/test/unit/UtilsTest.php
+++ b/test/unit/UtilsTest.php
@@ -112,6 +112,34 @@ class UtilsTest extends TestCase
         $this->assertEquals($isPrefixed, true);
     }
 
+    /**
+     * testIsAddress
+     * 
+     * @return void
+     */
+    public function testIsAddress()
+    {
+        $isAddress = Utils::isAddress('ca35b7d915458ef540ade6068dfe2f44e8fa733c');
+
+        $this->assertEquals($isAddress, true);
+
+        $isAddress = Utils::isAddress('0xca35b7d915458ef540ade6068dfe2f44e8fa733c');
+
+        $this->assertEquals($isAddress, true);
+
+        $isAddress = Utils::isAddress('0Xca35b7d915458ef540ade6068dfe2f44e8fa733c');
+
+        $this->assertEquals($isAddress, true);
+
+        $isAddress = Utils::isAddress('0XCA35B7D915458EF540ADE6068DFE2F44E8FA733C');
+
+        $this->assertEquals($isAddress, true);
+
+        $isAddress = Utils::isAddress('0xCA35B7D915458EF540ADE6068DFE2F44E8FA733C');
+
+        $this->assertEquals($isAddress, true);
+    }
+
     /**
      * testStripZero
      *