diff --git a/dlls/mshtml/htmlevent.c b/dlls/mshtml/htmlevent.c
index 5804615e1e8..22043ed03cb 100644
--- a/dlls/mshtml/htmlevent.c
+++ b/dlls/mshtml/htmlevent.c
@@ -42,6 +42,9 @@ struct event_target_t {
     handler_vector_t *event_table[EVENTID_LAST];
 };
 
+static const WCHAR beforeunloadW[] = {'b','e','f','o','r','e','u','n','l','o','a','d',0};
+static const WCHAR onbeforeunloadW[] = {'o','n','b','e','f','o','r','e','u','n','l','o','a','d',0};
+
 static const WCHAR blurW[] = {'b','l','u','r',0};
 static const WCHAR onblurW[] = {'o','n','b','l','u','r',0};
 
@@ -97,6 +100,7 @@ typedef struct {
 #define EVENT_BUBBLE             0x0002
 
 static const event_info_t event_info[] = {
+    {beforeunloadW, onbeforeunloadW, EVENT_DEFAULTLISTENER},
     {blurW,         onblurW,         EVENT_DEFAULTLISTENER},
     {changeW,       onchangeW,       EVENT_DEFAULTLISTENER|EVENT_BUBBLE},
     {clickW,        onclickW,        EVENT_DEFAULTLISTENER|EVENT_BUBBLE},
diff --git a/dlls/mshtml/htmlevent.h b/dlls/mshtml/htmlevent.h
index f1d208ca7f6..89d9526f5e1 100644
--- a/dlls/mshtml/htmlevent.h
+++ b/dlls/mshtml/htmlevent.h
@@ -17,6 +17,7 @@
  */
 
 typedef enum {
+    EVENTID_BEFOREUNLOAD,
     EVENTID_BLUR,
     EVENTID_CHANGE,
     EVENTID_CLICK,
@@ -67,3 +68,13 @@ static inline HRESULT get_doc_event(HTMLDocument *doc, eventid_t eid, VARIANT *v
 {
     return get_event_handler(&doc->event_target, eid, var);
 }
+
+static inline HRESULT set_window_event(HTMLWindow *window, eventid_t eid, VARIANT *var)
+{
+    return set_event_handler(&window->event_target, window->doc, eid, var);
+}
+
+static inline HRESULT get_window_event(HTMLWindow *window, eventid_t eid, VARIANT *var)
+{
+    return get_event_handler(&window->event_target, eid, var);
+}
diff --git a/dlls/mshtml/htmlwindow.c b/dlls/mshtml/htmlwindow.c
index 3a52db6607f..7827d51ccbd 100644
--- a/dlls/mshtml/htmlwindow.c
+++ b/dlls/mshtml/htmlwindow.c
@@ -512,15 +512,19 @@ static HRESULT WINAPI HTMLWindow2_get_onload(IHTMLWindow2 *iface, VARIANT *p)
 static HRESULT WINAPI HTMLWindow2_put_onbeforeunload(IHTMLWindow2 *iface, VARIANT v)
 {
     HTMLWindow *This = HTMLWINDOW2_THIS(iface);
-    FIXME("(%p)->(v(%d))\n", This, V_VT(&v));
-    return E_NOTIMPL;
+
+    TRACE("(%p)->(v(%d))\n", This, V_VT(&v));
+
+    return set_window_event(This, EVENTID_BEFOREUNLOAD, &v);
 }
 
 static HRESULT WINAPI HTMLWindow2_get_onbeforeunload(IHTMLWindow2 *iface, VARIANT *p)
 {
     HTMLWindow *This = HTMLWINDOW2_THIS(iface);
-    FIXME("(%p)->(%p)\n", This, p);
-    return E_NOTIMPL;
+
+    TRACE("(%p)->(%p)\n", This, p);
+
+    return get_window_event(This, EVENTID_BEFOREUNLOAD, p);
 }
 
 static HRESULT WINAPI HTMLWindow2_put_onunload(IHTMLWindow2 *iface, VARIANT v)