diff --git a/src/spellfile.c b/src/spellfile.c
index 24df042b764af79a22642b99efe35f044e3609f1..7a3b77660eebae2145b44e7bf19b2d4a5b212032 100644
--- a/src/spellfile.c
+++ b/src/spellfile.c
@@ -6216,6 +6216,12 @@ spell_add_word(
     int		i;
     char_u	*spf;
 
+    if (enc_utf8 && !utf_valid_string(word, NULL))
+    {
+	emsg(_(e_illegal_character_in_word));
+	return;
+    }
+    
     if (!valid_spell_word(word, word + len))
     {
 	emsg(_(e_illegal_character_in_word));