The 26-year-old, who is based at the Northern Snooker Centre in Leeds, beat off fierce competition at the new qualifying system, Q School, from over 100 players from around the globe to clinch one of four coveted tour places for 2011-12.
Grace booked his place at the World Snooker Academy, Sheffield, with a 4-1 defeat of China’s Zhang Anda, knocking in breaks of 71, 128 and 57.
It is a welcome return to the pro circuit for the Yorkshireman after he had one season on the main tour in 2008-09 after winning the European Championship.
“I only won a couple of matches in that season although I did have some narrow defeats – I played Jimmy White twice and lost 5-4 and 9-8,” said former Under-19 champion Grace.
“I’d like to think that I’m a better player now and I know what the standard is like.
“It’s unbelievable to be back on, especially as there are so many events now. My only target will be to stay on the tour and to enjoy it.
“I won my first match in Q School 4-3 on the pink and got better every match after that.”
Joining Grace on tour next season are Finland’s Robin Hull, Wiltshire’s Adam Wicheard and Andrew Norman, from Bristol.
There was also a strong Yorkshire representation when it came to referees at Q School.
These included Phil Hartley, a 57-year-old from Middlesbrough, and Sheffield duo Arnold Greenwood and Keith Sedgewick. All have many years’ experience officiating amateur tournaments.
O’Sullivan is back in Yorkshire on Thursday for a snooker legends night against Jimmy White at the revamped York Barbican.