Kacper Żuk (born 21 January 1999) is a former Polish professional tennis player.

Żuk has a career high ATP singles ranking of World No.

Additionally, he has reached 21 career doubles finals, with a record of 12 wins and 9 losses all but one occurring at the ITF Futures level.

[1] He ended the 2020 season with back-to-back ITF World Tennis Tour titles at Hamburg and Vale do Lobo.

3 male player in the semifinals against Frances Tiafoe and lost in straight sets.