diff --git a/heap/hp_hash.c b/heap/hp_hash.c
index 9e4636ebdc0..d643f776731 100644
--- a/heap/hp_hash.c
+++ b/heap/hp_hash.c
@@ -552,9 +552,9 @@ int hp_rec_key_cmp(HP_KEYDEF *keydef, const byte *rec1, const byte *rec2,
       if (cs->mbmaxlen > 1)
       {
         uint char_length= seg->length / cs->mbmaxlen;
-        char_length1= my_charpos(cs, pos1, pos1 + char_length1, char_length);
+        char_length1= my_charpos(cs, pos1, pos1 + char_length1, char_length1);
         set_if_smaller(char_length1, seg->length);
-        char_length2= my_charpos(cs, pos2, pos2 + char_length2, char_length);
+        char_length2= my_charpos(cs, pos2, pos2 + char_length2, char_length2);
         set_if_smaller(char_length2, seg->length);
       }
 
diff --git a/mysql-test/r/ctype_utf8.result b/mysql-test/r/ctype_utf8.result
index b8ff3c70aa1..3af13289478 100644
--- a/mysql-test/r/ctype_utf8.result
+++ b/mysql-test/r/ctype_utf8.result
@@ -950,3 +950,22 @@ hex(a)
 5B
 E880BD
 drop table t1;
+CREATE TABLE t1(id varchar(20) NOT NULL) DEFAULT CHARSET=utf8;
+INSERT INTO t1 VALUES ('xxx'), ('aa'), ('yyy'), ('aa');
+SELECT id FROM t1;
+id
+xxx
+aa
+yyy
+aa
+SELECT DISTINCT id FROM t1;
+id
+xxx
+aa
+yyy
+SELECT DISTINCT id FROM t1 ORDER BY id;
+id
+aa
+xxx
+yyy
+DROP TABLE t1;
diff --git a/mysql-test/t/ctype_utf8.test b/mysql-test/t/ctype_utf8.test
index 0a847057258..86de7d5d761 100644
--- a/mysql-test/t/ctype_utf8.test
+++ b/mysql-test/t/ctype_utf8.test
@@ -800,3 +800,16 @@ insert into t1 values (_utf8 0xe880bd);
 insert into t1 values (_utf8 0x5b);
 select hex(a) from t1;
 drop table t1;
+
+#
+# Test for bug #11484: wrong results for a DISTINCT varchar column in uft8. 
+#
+
+CREATE TABLE t1(id varchar(20) NOT NULL) DEFAULT CHARSET=utf8;
+INSERT INTO t1 VALUES ('xxx'), ('aa'), ('yyy'), ('aa');
+
+SELECT id FROM t1;
+SELECT DISTINCT id FROM t1;
+SELECT DISTINCT id FROM t1 ORDER BY id;
+
+DROP TABLE t1;