O'Sullivan becomes the first man since Stephen Hendry in 1996 to retain the title.
O'Sullivan edged ahead of surprise finalist Hawkins in yesterday's session before building on that this afternoon to take a 15-10 lead into the final session this evening.
'The Rocket' wasted no time in completing the job, winning his fifth title despite having taken a year out of the sport for personal reasons before arriving in Sheffield for the Championship.
O'Sullivan hit six century breaks during the final, more than any other player has ever managed in a final and the joint most by one player in a single match in World Championship history.
Those six treble-figure breaks also lifted him above the legendary Stephen Hendry as the player with the most 100+ breaks in the Crucible.
Speculation has raged over whether the enigmatic O'Sullivan, widely regarded as the greatest snooker player ever, will retire from the sport after his latest success.