diff --git a/mysql-test/r/func_gconcat.result b/mysql-test/r/func_gconcat.result
index 3cb8da7f63f..ef46d170bda 100644
--- a/mysql-test/r/func_gconcat.result
+++ b/mysql-test/r/func_gconcat.result
@@ -604,3 +604,19 @@ count(distinct (f1+1))
 1
 3
 drop table t1;
+create table t1 (f1 int unsigned, f2 varchar(255));
+insert into t1 values (1,repeat('a',255)),(2,repeat('b',255));
+select f2,group_concat(f1) from t1 group by f2;
+Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
+def	test	t1	t1	f2	f2	253	255	255	Y	0	0	8
+def					group_concat(f1)	252	400	1	Y	128	0	63
+f2	group_concat(f1)
+aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa	1
+bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb	2
+select f2,group_concat(f1) from t1 group by f2 order by 2;
+Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
+def	test	t1	t1	f2	f2	253	255	255	Y	0	0	8
+def				group_concat(f1)	group_concat(f1)	252	400	1	Y	144	0	63
+f2	group_concat(f1)
+aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa	1
+bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb	2
diff --git a/mysql-test/t/func_gconcat.test b/mysql-test/t/func_gconcat.test
index f116aa6f164..1bb49a312b8 100644
--- a/mysql-test/t/func_gconcat.test
+++ b/mysql-test/t/func_gconcat.test
@@ -390,4 +390,14 @@ insert into t1 values(1),(2),(3);
 select f1, group_concat(f1+1) from t1 group by f1 with rollup;
 select count(distinct (f1+1)) from t1 group by f1 with rollup;
 drop table t1;
+
+#
+# Bug#14169 type of group_concat() result changed to blob if tmp_table was used
+#
+create table t1 (f1 int unsigned, f2 varchar(255));
+insert into t1 values (1,repeat('a',255)),(2,repeat('b',255));
+--enable_metadata
+select f2,group_concat(f1) from t1 group by f2;
+select f2,group_concat(f1) from t1 group by f2 order by 2;
+--disable_metadata
 # End of 4.1 tests
diff --git a/sql/item_func.cc b/sql/item_func.cc
index d0d2eca7233..174a8c55d01 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -307,7 +307,7 @@ Field *Item_func::tmp_table_field(TABLE *t_arg)
     res= new Field_double(max_length, maybe_null, name, t_arg, decimals);
     break;
   case STRING_RESULT:
-    if (max_length > 255)
+    if (max_length/collation.collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB)
       res= new Field_blob(max_length, maybe_null, name, t_arg, collation.collation);
     else
       res= new Field_string(max_length, maybe_null, name, t_arg, collation.collation);
diff --git a/sql/item_sum.h b/sql/item_sum.h
index c972240fcba..0cc2a20faa3 100644
--- a/sql/item_sum.h
+++ b/sql/item_sum.h
@@ -729,6 +729,13 @@ class Item_func_group_concat : public Item_sum
   enum Sumfunctype sum_func () const {return GROUP_CONCAT_FUNC;}
   const char *func_name() const { return "group_concat"; }
   virtual Item_result result_type () const { return STRING_RESULT; }
+  enum_field_types field_type() const
+  {
+    if (max_length/collation.collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB)
+      return FIELD_TYPE_BLOB;
+    else
+      return MYSQL_TYPE_VAR_STRING;
+  }
   void clear();
   bool add();
   void reset_field();
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index d7aa617cffd..91fc808058f 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -4925,7 +4925,8 @@ static Field* create_tmp_field_from_item(THD *thd, Item *item, TABLE *table,
     if ((type= item->field_type()) == MYSQL_TYPE_DATETIME ||
         type == MYSQL_TYPE_TIME || type == MYSQL_TYPE_DATE)
       new_field= item->tmp_table_field_from_field_type(table);
-    else if (item->max_length/item->collation.collation->mbmaxlen > 255)
+    else if (item->max_length/item->collation.collation->mbmaxlen >
+             CONVERT_IF_BIGGER_TO_BLOB)
     {
       if (convert_blob_length)
         new_field= new Field_varstring(convert_blob_length, maybe_null,
@@ -5028,7 +5029,8 @@ Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type,
 	return new Field_longlong(item_sum->max_length,maybe_null,
 				  item->name,table,item->unsigned_flag);
       case STRING_RESULT:
-	if (item_sum->max_length > 255)
+	if (item_sum->max_length/item_sum->collation.collation->mbmaxlen >
+            CONVERT_IF_BIGGER_TO_BLOB)
         {
           if (convert_blob_length)
             return new Field_varstring(convert_blob_length, maybe_null,
diff --git a/sql/unireg.h b/sql/unireg.h
index 70df9a89c8f..3fb30315c81 100644
--- a/sql/unireg.h
+++ b/sql/unireg.h
@@ -60,6 +60,7 @@
 
 #define MAX_MBWIDTH		3		/* Max multibyte sequence */
 #define MAX_FIELD_CHARLENGTH	255
+#define CONVERT_IF_BIGGER_TO_BLOB 255
 /* Max column width +1 */
 #define MAX_FIELD_WIDTH		(MAX_FIELD_CHARLENGTH*MAX_MBWIDTH+1)