diff --git a/mysql-test/main/func_json.result b/mysql-test/main/func_json.result
index b3d7a1d2ed1..aa9c9cdc8b5 100644
--- a/mysql-test/main/func_json.result
+++ b/mysql-test/main/func_json.result
@@ -1328,5 +1328,19 @@ JSON_ARRAYAGG(col1)
 [{"color":"red", "size":1},{"color":"blue", "size":2}]
 drop table t1;
 #
+# MDEV-23029: JSON_OBJECTAGG returns NULL when used together with GROUP BY
+#
+CREATE TABLE t1 (e INT, a VARCHAR(255), v VARCHAR(255));
+INSERT INTO t1 VALUES (0, 'a1', '1') , (0, 'a2', '2') , (1, 'b1', '3');
+EXPLAIN SELECT B.e, JSON_OBJECTAGG(B.a, B.v) FROM t1 A, t1 B GROUP BY B.e;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	A	ALL	NULL	NULL	NULL	NULL	3	Using temporary; Using filesort
+1	SIMPLE	B	ALL	NULL	NULL	NULL	NULL	3	Using join buffer (flat, BNL join)
+SELECT B.e, JSON_OBJECTAGG(B.a, B.v) FROM t1 A, t1 B GROUP BY B.e;
+e	JSON_OBJECTAGG(B.a, B.v)
+0	{"a1":"1", "a1":"1", "a1":"1", "a2":"2", "a2":"2", "a2":"2"}
+1	{"b1":"3", "b1":"3", "b1":"3"}
+DROP TABLE t1;
+#
 # End of 10.5 tests
 #
diff --git a/mysql-test/main/func_json.test b/mysql-test/main/func_json.test
index 531f6cd758d..75a118a808f 100644
--- a/mysql-test/main/func_json.test
+++ b/mysql-test/main/func_json.test
@@ -826,6 +826,18 @@ insert into t1 values('{"color":"blue", "size":2}' );
 select JSON_ARRAYAGG(col1) from t1;
 drop table t1;
 
+--echo #
+--echo # MDEV-23029: JSON_OBJECTAGG returns NULL when used together with GROUP BY
+--echo #
+
+CREATE TABLE t1 (e INT, a VARCHAR(255), v VARCHAR(255));
+INSERT INTO t1 VALUES (0, 'a1', '1') , (0, 'a2', '2') , (1, 'b1', '3');
+
+EXPLAIN SELECT B.e, JSON_OBJECTAGG(B.a, B.v) FROM t1 A, t1 B GROUP BY B.e;
+SELECT B.e, JSON_OBJECTAGG(B.a, B.v) FROM t1 A, t1 B GROUP BY B.e;
+
+DROP TABLE t1;
+
 --echo #
 --echo # End of 10.5 tests
 --echo #
diff --git a/sql/item_jsonfunc.cc b/sql/item_jsonfunc.cc
index b9a84775311..fe3fae5840c 100644
--- a/sql/item_jsonfunc.cc
+++ b/sql/item_jsonfunc.cc
@@ -3725,6 +3725,7 @@ Item_func_json_objectagg::
 Item_func_json_objectagg(THD *thd, Item_func_json_objectagg *item)
   :Item_sum(thd, item)
 {
+  quick_group= FALSE;
   result.set_charset(collation.collation);
   result.append("{");
 }
diff --git a/sql/item_jsonfunc.h b/sql/item_jsonfunc.h
index 0408b3ad72f..69625831045 100644
--- a/sql/item_jsonfunc.h
+++ b/sql/item_jsonfunc.h
@@ -579,6 +579,7 @@ public:
   Item_func_json_objectagg(THD *thd, Item *key, Item *value) :
     Item_sum(thd, key, value)
   {
+    quick_group= FALSE;
     result.append("{");
   }