diff --git a/composer.json b/composer.json
index 1f960dc..3474a76 100644
--- a/composer.json
+++ b/composer.json
@@ -23,8 +23,8 @@
     "twig/twig": ">=1.35"
   },
   "require-dev": {
-    "phpunit/phpunit": "~6.0",
     "php-coveralls/php-coveralls": "^1.0",
+    "phpunit/phpunit": "^6.5",
     "squizlabs/php_codesniffer": "*"
   },
   "autoload": {
diff --git a/src/Fields/ChoiceField.php b/src/Fields/ChoiceField.php
index f17581d..7313139 100644
--- a/src/Fields/ChoiceField.php
+++ b/src/Fields/ChoiceField.php
@@ -41,7 +41,7 @@ public function validate($value)
     {
         parent::validate($value);
 
-        if (!$this->validValue($value)) {
+        if (!$this->isEmpty($value) && !$this->validValue($value)) {
             if (is_array($value)) {
                 $value_diff = array_diff($value, array_keys($this->choices));
                 $value = implode(', ', $value_diff);
diff --git a/tests/unit/Fields/ChoiceFieldTest.php b/tests/unit/Fields/ChoiceFieldTest.php
index 4fa6fcb..7ac4bf4 100644
--- a/tests/unit/Fields/ChoiceFieldTest.php
+++ b/tests/unit/Fields/ChoiceFieldTest.php
@@ -61,16 +61,6 @@ public function testValidateChoiceUnexistent()
         $this->field->validate("option2");
     }
 
-    /**
-     * @expectedException PHPForm\Exceptions\ValidationError
-     * @expectedExceptionMessage Select a valid choice. "empty string" is not one of the available choices.
-     */
-    public function testValidateChoiceEmpty()
-    {
-        $field = new ChoiceField(["choices" => array("option1" => "Option1")]);
-        $field->validate("");
-    }
-
     public function testValidateValidValue()
     {
         $this->assertNull($this->field->validate("option1"));