diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 8bebc34bd20..f8960dd6a80 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2001-02-05  Eli Zaretskii  <eliz@is.elta.co.il>
+
+	* textmodes/nroff-mode.el (nroff-mode): Set the SYNTAX-BEGIN part
+	of font-lock-defaults to backward-paragraph.
+
 2001-02-05  Gerd Moellmann  <gerd@gnu.org>
 
 	* mail/rmail.el (rmail-ignored-headers): Add X-Trace,
diff --git a/lisp/textmodes/nroff-mode.el b/lisp/textmodes/nroff-mode.el
index 8bd53920823..07cf36a31cf 100644
--- a/lisp/textmodes/nroff-mode.el
+++ b/lisp/textmodes/nroff-mode.el
@@ -113,7 +113,11 @@ closing requests for requests that are used in matched pairs."
     (modify-syntax-entry ?\n ">  1" nroff-mode-syntax-table))
   (set-syntax-table nroff-mode-syntax-table)
   (make-local-variable 'font-lock-defaults)
-  (setq font-lock-defaults '(nroff-font-lock-keywords nil t))
+  (setq font-lock-defaults
+	;; SYNTAX-BEGIN is set to backward-paragraph to avoid slow-down
+	;; near the end of large buffers due to searching to buffer's
+	;; beginning.
+	'(nroff-font-lock-keywords nil t nil backward-paragraph))
   (setq local-abbrev-table nroff-mode-abbrev-table)
   (make-local-variable 'nroff-electric-mode)
   (setq nroff-electric-mode nil)