Kien topped the ranking in the boys 13-14 years old platform event with 265.55 points.
His teammate Pham Thai Thien Bao came second, followed by Megat Syakir Hashim Megat of Malaysia.
The last medal of the team went to Bui Hong Giang who took the bronze in the girls 16-18 years old platform.
The Asian championship included swimming, diving, synchronised swimming, and water polo. Vietnam took part in the first two, and pocketed 15 gold, 21 silver and 30 bronze medals to take the fourth place overall.
The diving team won one gold, four silver and seven bronze medals, ranking fifth overall.
