diff --git a/src/ChangeLog b/src/ChangeLog
index 9867527e28f..082102bc3d8 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2013-12-06  Eli Zaretskii  <eliz@gnu.org>
+
+	* buffer.c (Fset_buffer_multibyte): Invalidate buffer caches.
+	(Bug#16070)
+
 2013-12-06  Dmitry Antipov  <dmantipov@yandex.ru>
 
 	* xterm.c (input_signal_count): Remove.
diff --git a/src/buffer.c b/src/buffer.c
index b40dc8cb3b7..e4a550fed95 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -2482,6 +2482,8 @@ current buffer is cleared.  */)
   if (narrowed)
     error ("Changing multibyteness in a narrowed buffer");
 
+  invalidate_buffer_caches (current_buffer, BEGV, ZV);
+
   if (NILP (flag))
     {
       ptrdiff_t pos, stop;