Pocock retired from international duty after the 2019 Rugby World Cup, having earned 78 caps for his country.
Now, the 32-year-old is stepping away from the game altogether, opting out of the final year of his contract at Japanese side Panasonic Wild Knights.
"While it was a tough decision, it really feels like the right one now and as a lot of former athletes talk about, it's not going to be smooth sailing but it's going to be a great challenge," Pocock said.
Pocock, who also represented Western Force and ACT Brumbies, steps away from the game with some self-confessed regrets.
He featured in three Rugby World Cups for the Wallabies but never got to lift the trophy, with his last attempt halted in a 40-16 quarter-final thrashing at the hands of England.
"On the day, we were fairly soundly beaten by a pretty good English team," he said.
"It certainly does [haunt you]. You wonder if you were on the other side of the draw, not losing that game to Wales (29-25), but that's sport.
"That's the great thing about sport – you get an opportunity and if you're not the most deserving on the day then that's what history records."