diff --git a/src/DI/Helpers.php b/src/DI/Helpers.php
index 968d38710..c906ba7fe 100644
--- a/src/DI/Helpers.php
+++ b/src/DI/Helpers.php
@@ -119,7 +119,7 @@ public static function autowireArguments(\ReflectionFunctionAbstract $method, ar
 					$optCount = 0;
 				}
 
-			} elseif ($parameter->isOptional() || $parameter->isDefaultValueAvailable()) {
+			} elseif (($class && $parameter->allowsNull()) || $parameter->isOptional() || $parameter->isDefaultValueAvailable()) {
 				// !optional + defaultAvailable = func($a = NULL, $b) since 5.4.7
 				// optional + !defaultAvailable = i.e. Exception::__construct, mysqli::mysqli, ...
 				$res[$num] = $parameter->isDefaultValueAvailable() ? $parameter->getDefaultValue() : NULL;
diff --git a/tests/DI/Helpers.autowireArguments.php71.phpt b/tests/DI/Helpers.autowireArguments.php71.phpt
new file mode 100644
index 000000000..2d5eb3749
--- /dev/null
+++ b/tests/DI/Helpers.autowireArguments.php71.phpt
@@ -0,0 +1,42 @@
+<?php
+
+/**
+ * Test: Nette\DI\Config\Helpers::autowireArguments()
+ * @phpversion 7.1
+ */
+
+use Nette\DI\Helpers;
+use Tester\Assert;
+
+
+require __DIR__ . '/../bootstrap.php';
+
+
+class Container
+{
+	function getByType($type)
+	{
+		return $type === 'Test' ? new Test : NULL;
+	}
+}
+
+class Test
+{
+	function method(Test $class, self $self, Undefined $nullable1 = NULL, int $nullable2 = NULL)
+	{}
+
+	function methodNullable(?Test $class, ?self $self, ?Undefined $nullable1, ?int $nullable2)
+	{}
+}
+
+$container = new Container;
+
+Assert::equal(
+	[new Test, new Test],
+	Helpers::autowireArguments(new ReflectionMethod('Test', 'method'), [], $container)
+);
+
+Assert::equal(
+	[new Test, new Test],
+	Helpers::autowireArguments(new ReflectionMethod('Test', 'methodNullable'), [], $container)
+);