On 17 May 2021, Australia named a 23-man preliminary squad for the tour with
Aaron Finch being named as their captain. On 8 June 2021, six more players were added to Australia's preliminary squad. Australia did not name individual squads for the ODI and T20I matches, opting instead to name a combined squad of 18 players for the tour.
Tanveer Sangha and
Nathan Ellis were named as reserve players. Ahead of the first ODI,
Alex Carey was named captain of Australia. On 25 July 2021, Australia's captain
Aaron Finch was ruled out of the ODI series due to an injury. On 18 May 2021,
Cricket West Indies (CWI) named a 18-man provisional squad for the T20I matches, with
Kieron Pollard captaining the team. On 7 July 2021, CWI named a 15-member squad for the ODI matches. Ahead of the third T20I,
Oshane Thomas was added to the West Indies' squad. For the fourth and fifth T20Is, CWI added
Akeal Hosein and
Kevin Sinclair to their squad. They replaced
Shimron Hetmyer and
Obed McCoy who both had minor injuries. For the last T20I, CWI added
Darren Bravo to their squad.
Roston Chase was ruled out of the ODI series, with
Hayden Walsh Jr. replacing him in the West Indies' ODI squad. ==Practice matches==