diff --git a/src/Eth.php b/src/Eth.php
index 93e2a5b..be4cadf 100644
--- a/src/Eth.php
+++ b/src/Eth.php
@@ -79,6 +79,16 @@ class Eth
                 ]
             ]
         ],
+        'eth_getBlockTransactionCountByNumber' => [
+            'params' => [
+                [
+                    'default' => 'latest',
+                    'validators' => [
+                        TagValidator::class, QuantityValidator::class,
+                    ]
+                ]
+            ]
+        ],
     ];
 
     /**
diff --git a/src/Validators/QuantityValidator.php b/src/Validators/QuantityValidator.php
index 27a127e..672b738 100644
--- a/src/Validators/QuantityValidator.php
+++ b/src/Validators/QuantityValidator.php
@@ -15,6 +15,6 @@ class QuantityValidator
     public static function validate($value)
     {
         // maybe change in_int and preg_match future
-        return (is_int($value) || preg_match('/^0x[a-fA-f0-9]+/', $value) >= 1);
+        return (is_int($value) || preg_match('/^0x[a-fA-f0-9]+$/', $value) >= 1);
     }
 }
\ No newline at end of file
diff --git a/test/unit/EthTest.php b/test/unit/EthTest.php
index 9700cb5..332fcea 100644
--- a/test/unit/EthTest.php
+++ b/test/unit/EthTest.php
@@ -287,6 +287,32 @@ class EthTest extends TestCase
         });
     }
 
+    /**
+     * testGetBlockTransactionCountByNumber
+     * 
+     * @return void
+     */    
+    public function testGetBlockTransactionCountByNumber()
+    {
+        $eth = $this->web3->eth;
+
+        $eth->getBlockTransactionCountByNumber('0x0', function ($err, $transactionCount) {
+            if ($err !== null) {
+                return $this->fail($err->getMessage());
+            }
+            if (isset($transactionCount->result)) {
+                var_dump($transactionCount->result);
+                $this->assertTrue(is_string($transactionCount->result));
+            } else {
+                if (isset($transactionCount->error)) {
+                    $this->fail($transactionCount->error->message);
+                } else {
+                    $this->assertTrue(true);
+                }
+            }
+        });
+    }
+
     /**
      * testUnallowedMethod
      *