Former Formula 1 driver Tim Schenken presented the Formula 2 champion with the prestigious award at Albert Park, home of the Australia Grand Prix, this morning.
Piastri is just the second driver to win the award twice, the other being Will Power, and the first to go back-to-back.
The award is one of Motorsport Australia's highest honours, recognising outstanding achievements and success by an Australian motorsport competitor at an international level.
Previous winners include Daniel Ricciardo, Mark Webber and Marcos Ambrose.
The consecutive Sir Jack Brabham Awards follow a remarkable run of titles for Piastri, who won the Formula Renault Eurocup in 2019, the FIA Formula 3 title in 2020 and the F2 titles in 2021.
He will spend 2022 working as Alpine's test and development driver ahead of a planned Formula 1 debut in 2023.
“A big thank you to the Motorsport Australia Board for choosing me as this year’s Sir Jack Brabham Award recipient – it’s quite special knowing that I am in the rare company of people to have won the award twice, with Will Power being the only other," said Piastri.
“While it might not directly compare to the thrill of winning races or the championship title, I’m still very appreciative of these awards because they are linked to my success and are a nice bonus for all my hard work.
“As for my on-track performances, I was amazed that I went back-to-back with Formula Renault and Formula 3, but to win each of top three junior categories was amazing - you really couldn’t have written the script of the past three years any better.
“I have had my time to celebrate but now I am fully focused on a big 2022 and I feel like I am peaking at the right time.”
Motorsport Australia president Andrew Fraser labelled Piastri a "once-in-a-generation" talent.
“To win this award once is a very special feat but to win it twice is a remarkable achievement and Oscar is a highly deserving recipient of the 2022 Sir Jack Brabham Award.” he said.
“Oscar is a once-in-a-generation driver and not many individuals come close to experiencing the sort of success this young man has accumulated over the years.
“I wish him all the best for his year as Alpine’s F1 reserve driver and hopefully we will be seeing him in the Formula 1 world championship sooner rather than later.”
Sir Jack Brabham Award winners
2021: Oscar Piastri
2020: Oscar Piastri
2018: Will Power
2017: Matthew Campbell
2014: Daniel Ricciardo
2012: David Brabham
2011: Tony Gaze, DFC & Two Bars, OAM
2009: Marcos Ambrose
2009: Mark Webber AO
2007: Will Power
2006: Cody Crocker
2006: Ben Atkinson
