diff --git a/src/pocketmine/block/Block.php b/src/pocketmine/block/Block.php
index 5646c8af17..0ed6eb8033 100644
--- a/src/pocketmine/block/Block.php
+++ b/src/pocketmine/block/Block.php
@@ -69,7 +69,7 @@ class Block extends Position implements BlockIds, Metadatable{
 	/** @var int|null */
 	protected $itemId;
 
-	/** @var AxisAlignedBB */
+	/** @var AxisAlignedBB|null */
 	protected $boundingBox = null;