diff --git a/Tests/Unit/EnumerableTest.php b/Tests/Unit/EnumerableTest.php
index d1d0c3d..dd2a541 100644
--- a/Tests/Unit/EnumerableTest.php
+++ b/Tests/Unit/EnumerableTest.php
@@ -617,6 +617,15 @@ function testOfType()
         $this->assertEnumValuesEquals(
             [ new Exception ],
             $a->ofType('Exception'));
+
+        // ofType (subclass)
+        $derivedException = new class extends Exception { };
+        $this->assertEnumValuesSame(
+            [ $derivedException ],
+            E::from([ $derivedException ])->ofType(Exception::class));
+        $this->assertEnumValuesSame(
+            [ $derivedException ],
+            E::from([ $derivedException ])->ofType(\Throwable::class));
     }
 
     /** @covers \YaLinqo\Enumerable::select
diff --git a/YaLinqo/Enumerable.php b/YaLinqo/Enumerable.php
index 872f7c9..fc865d6 100644
--- a/YaLinqo/Enumerable.php
+++ b/YaLinqo/Enumerable.php
@@ -104,7 +104,7 @@ public function cast(string $type): Enumerable
      * Filters the elements of a sequence based on a specified type.
      * <p><b>Syntax</b>: ofType (type)
      * <p>The ofType method returns only elements of the specified type. To instead receive an error if an element cannot be cast, use {@link cast}.
-     * @param string $type The type to filter the elements of the sequence on. Can be either class name or one of the predefined types: array, int (integer, long), callable (callable), float (real, double), null, string, object, numeric, scalar.
+     * @param string $type The type to filter the elements of the sequence on. Can be a class or interface name (including subclasses and implementations) or one of the predefined types: array, int (integer, long), callable (callable), float (real, double), null, string, object, numeric, scalar.
      * @return Enumerable A sequence that contains elements from the input sequence of the specified type.
      * @package YaLinqo\Projection and filtering
      */
@@ -135,7 +135,7 @@ public function ofType(string $type): Enumerable
             case 'string':
                 return $this->where(function($v) { return is_string($v); });
             default:
-                return $this->where(function($v) use ($type) { return is_object($v) && get_class($v) === $type; });
+                return $this->where(function($v) use ($type) { return is_object($v) && $v instanceof $type; });
         }
     }