diff --git a/sw/source/ui/uno/unotxdoc.cxx b/sw/source/ui/uno/unotxdoc.cxx
index ef09ecf5a026..52d989de90e7 100644
--- a/sw/source/ui/uno/unotxdoc.cxx
+++ b/sw/source/ui/uno/unotxdoc.cxx
@@ -3033,6 +3033,12 @@ uno::Reference< text::XFlatParagraphIterator > SAL_CALL SwXTextDocument::getFlat
     throw ( uno::RuntimeException )
 {
     SolarMutexGuard aGuard;
+    if (!IsValid())
+    {
+        throw DisposedException("SwXTextDocument not valid",
+                static_cast<XTextDocument*>(this));
+    }
+
     return new SwXFlatParagraphIterator( *pDocShell->GetDoc(), nTextMarkupType, bAutomatic );
 }