diff --git a/README.md b/README.md
index a7b79b9..ba64947 100644
--- a/README.md
+++ b/README.md
@@ -52,6 +52,7 @@ Redis command                                    | Description
 **HGETALL** *key*                                | Gets all the fields and values in a hash
 **HMSET** *key* *array\<field, value\>*          | Sets each value in the corresponding field
 **HSET** *key* *field* *value*                   | Sets the string value of a hash field
+**HSETNX** *key* *field* *value*                 | Sets field in the hash stored at key to value, only if field does not yet exist
 **LINDEX** *key* *index*                         | Returns the element at index *index* in the list stored at *key*
 **LLEN** *key*                                   | Returns the length of the list stored at *key*
 **LPUSH** *key* *value* *[value ...]*            | Pushs values at the head of a list
diff --git a/src/M6Web/Component/RedisMock/RedisMock.php b/src/M6Web/Component/RedisMock/RedisMock.php
index 4fa5718..4f9289f 100644
--- a/src/M6Web/Component/RedisMock/RedisMock.php
+++ b/src/M6Web/Component/RedisMock/RedisMock.php
@@ -548,6 +548,27 @@ public function hset($key, $field, $value)
         return $this->returnPipedInfo((int) $isNew);
     }
 
+    public function hsetnx($key, $field, $value)
+    {
+        $this->deleteOnTtlExpired($key);
+
+        if (isset(self::$data[$key]) && !is_array(self::$data[$key])) {
+            return $this->returnPipedInfo(null);
+        }
+
+        $isNew = !isset(self::$data[$key][$field]);
+
+        if ($isNew) {
+            self::$data[$key][$field] = $value;
+            self::$dataTypes[$key]    = 'hash';
+            if (array_key_exists($key, self::$dataTtl)) {
+                unset(self::$dataTtl[$key]);
+            }
+        }
+
+        return $this->returnPipedInfo((int) $isNew);
+    }
+
     public function hmset($key, $pairs)
     {
         $this->deleteOnTtlExpired($key);
diff --git a/tests/units/RedisMock.php b/tests/units/RedisMock.php
index e5e7278..e60ddd5 100644
--- a/tests/units/RedisMock.php
+++ b/tests/units/RedisMock.php
@@ -1160,6 +1160,17 @@ public function testHSetHMSetHGetHDelHExistsHGetAll()
                 'raoul' => null,
                 'test1' => null,
             ));
+        sleep(2);
+        $this->assert
+            ->integer($redisMock->hsetnx('mykey', 'field', 'my value'))
+                ->isEqualTo(1)
+            ->integer($redisMock->hsetnx('mykey', 'field2', 'second value'))
+                ->isEqualTo(1)
+            ->integer($redisMock->hsetnx('mykey', 'field', 'override value'))
+                ->isEqualTo(0)
+            ->integer($redisMock->del('mykey'))
+                ->isEqualTo(2)
+        ;
     }
 
     public function testLLen()