The Rocket had gone into the final session holding a 16-8 lead just two frames away from the title after demolishing Dott 7-1 in the afternoon.
And the action was all over in barely 20 minutes as O'Sullivan began with a 92 break in frame 25 and then made sure of victory with two runs of 33.
O'Sullivan said: "If it had been closer I would have been a bit more emotional. It was a little bit of an anti-climax in the end but Graeme took me all way.
"At 5-0 down I was thinking 'this could be 18-0 to him' so I was pleased I got going and turned it around."
O'Sullivan paid tribute to Ray Reardon, who has been working on the tactical side of the master potter's game.
"My cueing hasn't been to highest standards, I cued well in spells but Ray came down and added a new dimension to my game. That's where I need to develop, there's still room for improvement and I'll keep going and going.
"People were saying it would be a one-sided final but I knew it wasn't going to be. Graeme's beaten John Higgins, one of the greats of all-time, and Matthew Stevens, who always does well here."
Dott, who raced into a 5-0 lead but was unable to live with O'Sullivan yesterday, added: "I've learned today that Ronnie's phenomenally good, in this afternoon's session he was dynamite. But I'll believe in myself a bit more now."
A visibly moved O'Sullivan will now look at how he can build on this latest success, and dedicated the title to his father, serving a life sentence in prison for murder.
He added: "I'm not too sure where I go from here, I'm just going to enjoy the moment, take some time off in the summer. I just want to keep improving. I just want to say to my dad, this one's for him. He's my man."
In addition to the £250,000 first prize, O'Sullivan has also regained the number one spot in the rankings thanks to his semi-final win over Stephen Hendry.
For Dott there was the consolation of a cheque for £125,000 and regaining his place back in the top 16.
O'Sullivan began the day with the match still in the balance as he was only holding a narrow 9-7 advantage. But he reeled off a series of impressive breaks to claim seven of the eight frames in the afternoon as Dott failed to repeat his standards of the opening day.
The early exchanges of the opening frame of the day had been tentative, and there was a bout of safety play lasting nearly 10 minutes before O'Sullivan took advantage of a red hanging over the yellow pocket.
The Rocket compiled 41 before playing safe and another run of 30 was sufficient to seal the frame.
For the first time it looked as if Dott was beginning to run out of steam after his exertions. He made a hash of an attempted safety shot to let O'Sullivan in for what quickly became a realistic chance for a 147.
O'Sullivan landed the first five reds and blacks but then inexplicably he missed a simple red.
Dott was unable to take advantage as he missed the same ball into the opposite black pocket and a 45 from O'Sullivan extended his advantage to 11-7.
But Dott pulled himself together in the next with an excellent break of 106 - the highest break of the match to show O'Sullivan that he should not be totally written off.
It was only his second ton of the championship compared with the 13 notched up by O'Sullivan.
Dott pulled out a couple of superb long reds in the final frame before the mid-session interval, the second of which started him off on a run of 29.
But then he missed a straightforward black off its spot and O'Sullivan needed no second invitation to clear up with 65 .
Dott found it difficult to contain O'Sullivan when the players returned after the interval and an 85 clearance set the tone.
A 62 was sufficient to win frame 22, and runs of 46 and 32 took the next out of the reach of Dott and then O'Sullivan completed a post-interval whitewash with a 61.