2021 Australian Open – Mixed doubles

Two-time defending champion Barbora Krejčíková and her partner Rajeev Ram defeated Samantha Stosur and Matthew Ebden in the final, 6–1, 6–4 to win the mixed doubles tennis title at the 2021 Australian Open. It was the pair's second major mixed doubles title as a team, after their first at the 2019 Australian Open. They saved a match point en route to the title, in the second round against Ena Shibahara and Ben McLachlan.

Krejčíková and Nikola Mektić were the defending champions, but chose to play separately this year. Mektić partnered Barbora Strýcová, but was defeated in the first round by Hayley Carter and Sander Gillé.

After not being held at the 2020 US Open and postponed 2020 French Open due to the COVID-19 pandemic, this year's tournament marked the return of mixed doubles to a Grand Slam tournament.

Seeds
• # 🇨🇿 Barbora Strýcová / Nikola Mektić (first round)

• # 🇺🇸 Nicole Melichar / 🇨🇴 Robert Farah (second round, withdrew)

• # 🇨🇦 Gabriela Dabrowski / Mate Pavić (quarterfinals)

• # Chan Hao-ching / 🇨🇴 Juan Sebastián Cabal (first round)

• # Demi Schuurs /  Wesley Koolhof (first round)

• # 🇨🇿 Barbora Krejčíková / 🇺🇸 Rajeev Ram (champions)

• # Latisha Chan /  Ivan Dodig (first round)

• # 🇧🇷 Luisa Stefani / 🇧🇷 Bruno Soares (second round)

Wild cards
• 🇺🇸 Asia Muhammad / 🇦🇺 Luke Saville

• 🇦🇺 Ellen Perez / 🇦🇺 Andrew Harris

• 🇦🇺 Ivana Popovic / 🇦🇺 Aleksandar Vukic

• 🇦🇺 Arina Rodionova / 🇦🇺 Max Purcell

• 🇦🇺 Storm Sanders / 🇦🇺 Marc Polmans

• 🇦🇺 Astra Sharma / 🇦🇺 John-Patrick Smith

• 🇦🇺 Samantha Stosur / 🇦🇺 Matthew Ebden

• 🇦🇺 Belinda Woolcock / 🇦🇺 John Peers

Alternate pairs
• 🇺🇸 Hayley Carter / 🇧🇪 Sander Gillé

Withdrawals
• 🇦🇷 Nadia Podoroska / 🇦🇷 Horacio Zeballos