diff --git a/lisp/gnus/nndoc.el b/lisp/gnus/nndoc.el
index 79518bb4f81..9d5e3900e8d 100644
--- a/lisp/gnus/nndoc.el
+++ b/lisp/gnus/nndoc.el
@@ -352,6 +352,7 @@ from the document.")
 	    nndoc-group-alist)
       (setq nndoc-dissection-alist nil)
       (with-current-buffer nndoc-current-buffer
+	(set-buffer-multibyte nil)
 	(erase-buffer)
 	(condition-case error
 	    (if (and (stringp nndoc-address)