The world number 24, who reached the Melbourne final in 2024, took a break from the sport last year after opting to undergo arthroscopic surgery on her right elbow.
She missed the US Open before returning to action at the China Open in September, where she was forced to retire from her third-round match due to pain in her elbow.
"Making this decision has been incredibly difficult for me. Melbourne is my 'lucky place', where I won my first Grand Slam main draw match and where I had my best experience," China's Zheng said in a statement on Instagram.
"I have a special connection to this place, and I was very eager to start my new season at the Melbourne Park."
The season's opening Grand Slam begins on January 18.