The Swiss won the title at Melbourne Park in 2014, defeating Rafael Nadal.
It was his first Grand Slam triumph and he peaked at world number three with the victory, later adding major titles at Roland Garros in 2015 and the US Open a year later.
"I'm incredibly grateful to receive a wildcard into the Australian Open in 2025," said Wawrinka, who has battled injuries in recent years and had drifted down the rankings.
"Melbourne holds such a special place in my heart - it's where I won my first Grand Slam and is one of the greatest milestones of my career."
Eight Australians also won wildcards, including Daria Saville and Ajla Tomljanovic.
Chinese veteran Zhang Shuai and Thailand's Kasidit Samrej had already been granted main draw wildcard entry after winning an Asia-Pacific playoff.
The opening Grand Slam of 2025 runs from January 12-26.