diff --git a/layout/base/nsDocumentViewer.cpp b/layout/base/nsDocumentViewer.cpp
index 0035a2f0c66..a5eadd33539 100644
--- a/layout/base/nsDocumentViewer.cpp
+++ b/layout/base/nsDocumentViewer.cpp
@@ -33,6 +33,7 @@
 #include "nsIDOMHTMLElement.h"
 #include "nsContentUtils.h"
 #include "nsLayoutStylesheetCache.h"
+#include "mozilla/a11y/DocAccessible.h"
 #include "mozilla/BasicEvents.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/dom/EncodingUtils.h"
@@ -1549,6 +1550,16 @@ nsDocumentViewer::Destroy()
     // cache ourselves.
     shEntry->SyncPresentationState();
 
+    // Shut down accessibility for the document before we start to tear it down.
+#ifdef ACCESSIBILITY
+    if (mPresShell) {
+      a11y::DocAccessible* docAcc = mPresShell->GetDocAccessible();
+      if (docAcc) {
+        docAcc->Shutdown();
+      }
+    }
+#endif
+
     // Break the link from the document/presentation to the docshell, so that
     // link traversals cannot affect the currently-loaded document.
     // When the presentation is restored, Open() and InitInternal() will reset