diff --git a/doctrine-mapping.xsd b/doctrine-mapping.xsd
index 3d6e3457f..86b3dd1ed 100644
--- a/doctrine-mapping.xsd
+++ b/doctrine-mapping.xsd
@@ -540,7 +540,6 @@
     </xs:sequence>
     <xs:attribute name="target-entity" type="xs:string" use="required" />
     <xs:attribute name="field" type="xs:NMTOKEN" use="required" />
-    <xs:attribute name="orphan-removal" type="xs:boolean" default="false" />
     <xs:attribute name="fetch" type="orm:fetch-type" default="LAZY" />
     <xs:attribute name="inversed-by" type="xs:NMTOKEN" />
     <xs:anyAttribute namespace="##other"/>