diff --git a/array.c b/array.c
index e776ebdc6a..1c94396907 100644
--- a/array.c
+++ b/array.c
@@ -3487,6 +3487,7 @@ rb_ary_uniq_bang(VALUE ary)
 	ARY_SET_LEN(ary, 0);
 	if (ARY_SHARED_P(ary) && !ARY_EMBED_P(ary)) {
 	    rb_ary_unshare(ary);
+	    FL_SET_EMBED(ary);
 	}
 	ary_resize_capa(ary, i);
 	st_foreach(RHASH_TBL(hash), push_value, ary);