O'Sullivan was crowned Betfred.com World Champion last Monday and also won the PartyPoker.com Premier League, PartyPoker.net German Masters and two Players Tour Championship events during a prolific season.
The 36-year-old from Chigwell was also voted Snooker Writers Player of the Year by the sport's leading journalists.
The Fans Player of the Year award, voted by thousands of fans from around the world, went to Judd Trump. Snooker's young sensation won the williamhill.com UK Championship last December as well as two PTC events.
Rookie of the Year went to Belgium's 17-year-old wonderkid Luca Brecel, who recently became the youngest player ever to compete at the Crucible.
Stuart Bingham took the Performance of the Year award for capturing his first world ranking title by beating Mark Williams 9-8 in the final of the Australian Goldfields Open.
The Magic Moment award went to Stephen Hendry for his magnificent 147 maximum break at the Crucible, which came just days before he announced his retirement.
Four players were inducted into snooker's Hall of Fame; those who had won the World Championship on more than one occasion who had not already been inducted. They were Walter Donaldson, Mark Williams, John Higgins and Ronnie O'Sullivan.
Full list of awards:
World Snooker Player of the Year: Ronnie O'Sullivan
Snooker Writers Player of the Year: Ronnie O'Sullivan
Fans Player of the Year: Judd Trump
Rookie of the Year: Luca Brecel
Performance of the Year: Stuart Bingham
Magic Moment of the Year: Stephen Hendry's 147
147 Club (players making a 147 during the season): Ronnie O'Sullivan, Mike Dunn, David Gray, Ricky Walden, Ding Junhui, Jamie Cope, Matthew Stevens, Marco Fu, Robert Milkins, Stephen Hendry
Hall of Fame inductees: Walter Donaldson, Mark Williams, John Higgins, Ronnie O'Sullivan.
It was revealed at the awards ceremony at the Dorchester Hotel that over £110,000 has been raised this season for Haven House, including £25,000 donated by Betfred.
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