Cheng Tsz Sum (Chinese: 鄭子森; born 20 March 1999) is a Hong Kong professional footballer who currently plays as a midfielder for Hong Kong Premier League club Tai Po.

On 5 August 2017, Cheng was unveiled as part of Lee Man's inaugural squad.

[1] On 31 July 2018, Cheng was named as one of Tai Po's summer signings.

[2] On 1 July 2020, Eastern announced that Cheng would join the club.

[5] This biographical article related to Hong Kong association football is a stub.