| Cheng Tsz Sum | |
| Fullname: | Cheng Tsz Sum |
| Birth Date: | 20 March 1999 |
| Birth Place: | Hong Kong |
| Height: | 1.77m |
| Position: | Left midfielder |
| Currentclub: | Tai Po |
| Clubnumber: | 99 |
| Youthyears1: | 2012–2017 |
| Youthclubs1: | Kwai Tsing |
| Years1: | 2017 |
| Caps1: | 0 |
| Goals1: | 0 |
| Clubs1: | Rangers |
| Years2: | 2017–2018 |
| Caps2: | 1 |
| Goals2: | 0 |
| Clubs2: | Lee Man |
| Years3: | 2018–2020 |
| Caps3: | 1 |
| Goals3: | 0 |
| Clubs3: | Tai Po |
| Years4: | 2020–2021 |
| Caps4: | 2 |
| Goals4: | 0 |
| Clubs4: | Eastern |
| Years5: | 2021–2022 |
| Caps5: | 1 |
| Goals5: | 0 |
| Clubs5: | Rangers |
| Years6: | 2022– |
| Caps6: | 27 |
| Goals6: | 1 |
| Clubs6: | Tai Po |
| Nationalyears1: | 2017 |
| Nationalteam1: | Hong Kong U-19 |
| Nationalcaps1: | 1 |
| Nationalgoals1: | 0 |
| Nationalyears2: | 2021 |
| Nationalteam2: | Hong Kong U-22 |
| Nationalcaps2: | 2 |
| Nationalgoals2: | 0 |
| Club-Update: | 7 May 2023 |
| Nationalteam-Update: | 23 October 2021 |
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.[3]
On 6 September 2021, Cheng rejoined Rangers.[4]
On 8 August 2022, Cheng returned to Tai Po.[5]