Kai Trewin (born 18 May 2001) is an Australian professional soccer player who plays as a centre back for A-League Men club Melbourne City.

[1] On 6 March 2020, Trewin made his professional debut for Brisbane Roar in a league match against Western Sydney Wanderers, replacing Scott McDonald in the 92nd minute as the Roar won 3–1.

[2] On 17 May 2024, it was announced that Trewin would join fellow A-League Men club Melbourne City on a permanent deal on 1 July, signing a three-year contract.

[3] Trewin has represented Australia at various youth levels.

Brisbane Roar Australia U20 Australia U17