2021 Australian Open – Wheelchair quad doubles
Dylan Alcott and Heath Davidson were the three-time defending champions and successfully defended their title, defeating Andy Lapthorne and David Wagner in the final, 6–2, 3–6, [10–7]. The Wheelchair Quad Doubles competition, consisting of a semifinal round and a championship match, began on 15 February. The competition features the same field of eight players contesting the Wheelchair Quad Singles competition. Two of the tournament's four pairs were seeded, with the Australian duo of Dylan Alcott and Heath Davidson receiving the top seed and the pair of Andy Lapthorne and David Wagner getting  the No. 2 seed. Both seeded pairs won their semifinal matchups in straight sets; Alcott/Davidson defeated Sam Schröder/Niels Vink and Lapthorne/Wagner defeated Koji Sugeno/Nicholas Taylor. The championship match, a rematch of the 2020 final, was held on 16 February with Alcott and Davidson winning the final in a tiebreaker.