diff --git a/src/popupwin.c b/src/popupwin.c
index ca75181..9d801ea 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -2969,8 +2969,14 @@
 
 	// Title goes on top of border or padding.
 	if (wp->w_popup_title != NULL)
-	    screen_puts(wp->w_popup_title, wp->w_winrow, wp->w_wincol + 1,
+	{
+	    int	    len = (int)STRLEN(wp->w_popup_title) + 1;
+	    char_u  *title = alloc(len);
+
+	    trunc_string(wp->w_popup_title, title, total_width - 2, len);
+	    screen_puts(title, wp->w_winrow, wp->w_wincol + 1,
 		    wp->w_popup_border[0] > 0 ? border_attr[0] : popup_attr);
+	}
 
 	// Compute scrollbar thumb position and size.
 	if (wp->w_has_scrollbar)