--- a/src/os_win32.c
+++ b/src/os_win32.c
@@ -1231,6 +1231,100 @@ mch_bevalterm_changed(void)
 }
 # endif
 
+
+/*
+ * Win32 console mouse scroll event handler.
+ * Loosely based on the _OnMouseWheel() function in gui_w32.c
+ *
+ * This encodes the mouse scroll direction and keyboard modifiers into
+ * g_nMouseClick, and the mouse position into g_xMouse and g_yMouse
+ *
+ * The direction of the scroll is decoded from two fields of the win32 console
+ * mouse event record;
+ *    1. The axis - vertical or horizontal flag - from dwEventFlags, and
+ *    2. The sign - positive or negative (aka delta flag) - from dwButtonState
+ *
+ * When scroll axis is HORIZONTAL
+ *    -  If the high word of the dwButtonState member contains a positive
+ *	 value, the wheel was rotated to the right.
+ *    -  Otherwise, the wheel was rotated to the left.
+ * When scroll axis is VERTICAL
+ *    -  If the high word of the dwButtonState member contains a positive value,
+ *       the wheel was rotated forward, away from the user.
+ *    -  Otherwise, the wheel was rotated backward, toward the user.
+ */
+    static void
+decode_mouse_wheel(MOUSE_EVENT_RECORD *pmer)
+{
+    win_T   *wp;
+    int	    horizontal = (pmer->dwEventFlags == MOUSE_HWHEELED);
+    int	    zDelta = pmer->dwButtonState;
+
+    g_xMouse = pmer->dwMousePosition.X;
+    g_yMouse = pmer->dwMousePosition.Y;
+
+#ifdef FEAT_PROP_POPUP
+    int lcol;
+    int lrow;
+    lcol = g_xMouse;
+    lrow = g_yMouse;
+    wp = mouse_find_win(&lrow, &lcol, FAIL_POPUP);
+    if (wp != NULL && popup_is_popup(wp))
+    {
+	g_nMouseClick = -1;
+	cmdarg_T cap;
+	oparg_T oa;
+	CLEAR_FIELD(cap);
+	clear_oparg(&oa);
+	cap.oap = &oa;
+	if (horizontal)
+	{
+	    cap.arg = zDelta < 0 ? MSCR_LEFT : MSCR_RIGHT;
+	    cap.cmdchar = zDelta < 0 ? K_MOUSELEFT : K_MOUSERIGHT;
+	}
+	else
+	{
+	    cap.cmdchar = zDelta < 0 ? K_MOUSEUP : K_MOUSEDOWN;
+	    cap.arg = zDelta < 0 ? MSCR_UP : MSCR_DOWN;
+	}
+
+	// Mouse hovers over popup window, scroll it if possible.
+	mouse_row = wp->w_winrow;
+	mouse_col = wp->w_wincol;
+	nv_mousescroll(&cap);
+	update_screen(0);
+	setcursor();
+	out_flush();
+	return;
+    }
+#endif
+    mouse_col = g_xMouse;
+    mouse_row = g_yMouse;
+
+    char_u modifiers = 0;
+    char_u direction = 0;
+
+    // Decode the direction into an event that Vim can process
+    if (horizontal)
+	direction = zDelta >= 0 ? KE_MOUSELEFT : KE_MOUSERIGHT;
+    else
+	direction = zDelta >= 0 ? KE_MOUSEDOWN : KE_MOUSEUP;
+
+    // Decode the win32 console key modifers into Vim mouse modifers.
+    if (pmer->dwControlKeyState & SHIFT_PRESSED)
+	modifiers |= MOD_MASK_SHIFT; //MOUSE_SHIFT;
+    if (pmer->dwControlKeyState & (RIGHT_CTRL_PRESSED | LEFT_CTRL_PRESSED))
+	modifiers |= MOD_MASK_CTRL; //MOUSE_CTRL;
+    if (pmer->dwControlKeyState & (RIGHT_ALT_PRESSED  | LEFT_ALT_PRESSED))
+	modifiers |= MOD_MASK_ALT; // MOUSE_ALT;
+
+    // add (bitwise or) the scroll direction and the key modifier chars
+    // together.
+    g_nMouseClick = ((direction << 8) | modifiers);
+
+    return;
+}
+
 /*
  * Decode a MOUSE_EVENT.  If it's a valid event, return MOUSE_LEFT,
  * MOUSE_MIDDLE, or MOUSE_RIGHT for a click; MOUSE_DRAG for a mouse
@@ -1304,6 +1398,13 @@ decode_mouse_event(
     if (g_nMouseClick != -1)
 	return TRUE;
 
+    if (pmer->dwEventFlags == MOUSE_WHEELED
+				       || pmer->dwEventFlags == MOUSE_HWHEELED)
+    {
+	decode_mouse_wheel(pmer);
+	return TRUE;  // we now should have a mouse scroll in g_nMouseClick
+    }
+
     nButton = -1;
     g_xMouse = pmer->dwMousePosition.X;
     g_yMouse = pmer->dwMousePosition.Y;
@@ -1939,12 +2040,34 @@ mch_inchar(
 		fprintf(fdDump, "{%02x @ %d, %d}",
 			g_nMouseClick, g_xMouse, g_yMouse);
 # endif
-	    typeahead[typeaheadlen++] = ESC + 128;
-	    typeahead[typeaheadlen++] = 'M';
-	    typeahead[typeaheadlen++] = g_nMouseClick;
-	    typeahead[typeaheadlen++] = g_xMouse + '!';
-	    typeahead[typeaheadlen++] = g_yMouse + '!';
-	    g_nMouseClick = -1;
+	    char_u modifiers = ((char_u *)(&g_nMouseClick))[0];
+	    char_u scroll_dir = ((char_u *)(&g_nMouseClick))[1];
+
+	    if (scroll_dir == KE_MOUSEDOWN
+		    || scroll_dir == KE_MOUSEUP
+		    || scroll_dir == KE_MOUSELEFT
+		    || scroll_dir == KE_MOUSERIGHT)
+	    {
+		if (modifiers > 0)
+		{
+		    typeahead[typeaheadlen++] = CSI;
+		    typeahead[typeaheadlen++] = KS_MODIFIER;
+		    typeahead[typeaheadlen++] = modifiers;
+		}
+		typeahead[typeaheadlen++] = CSI;
+		typeahead[typeaheadlen++] = KS_EXTRA;
+		typeahead[typeaheadlen++] = scroll_dir;
+		g_nMouseClick = -1;
+	    }
+	    else
+	    {
+		typeahead[typeaheadlen++] = ESC + 128;
+		typeahead[typeaheadlen++] = 'M';
+		typeahead[typeaheadlen++] = g_nMouseClick;
+		typeahead[typeaheadlen++] = g_xMouse + '!';
+		typeahead[typeaheadlen++] = g_yMouse + '!';
+		g_nMouseClick = -1;
+	    }
 	}
 	else
 	{
@@ -8361,7 +8484,7 @@ stop_timeout(void)
 {
     if (timer_active)
     {
-        BOOL ret = DeleteTimerQueueTimer(NULL, timer_handle, NULL);
+	BOOL ret = DeleteTimerQueueTimer(NULL, timer_handle, NULL);
 	timer_active = FALSE;
 	if (!ret && GetLastError() != ERROR_IO_PENDING)
 	{