Overall, the city's swimmers have claimed a record nine medals in Inner Mongolia.
Their previous best was eight medals which was achieved two years ago. They finished the Games here with one gold, four silver and four bronze medals.
Cliff Ching Kim-fu, Damien Ma Chi-wang, Cheng Ka-chun and multi-medal-winning team captain Kent Cheung Kin-tat said farewell to the pool by claiming an impressive second place behind Beijing.
Beijing's winning time in the boys' 4x100m medley relay was 3 minutes, 48.43 seconds, while Hong Kong clocked 3:59.76. Cliff's backstroke leg was followed by breaststroker Damien, then Ka-chun did the butterfly before Kent finished off with the freestyle.
Kent and Ka-chun also bade a final farewell to the Games, as they both begin university studies in September.