The victory gives Wozniacki, also champion in Tokyo in 2010, her first title of the year. The Dane had lost all six of her previous finals in 2017.
"This was my seventh final of the year -- it gets harder to get that last win," said world No. 6 Wozniacki, who has now won at least one title every year since 2008.
The first set lasted only 20 minutes as Pavlyuchenkova struggled to get a foothold.
She started the final with 35 double faults in four matches to her name this week, and extended that to 36 with her first serve of the match. Things did not immediately improve.
Wozniacki had crushed world No.1 Garbine Muguruza 6-2, 6-0 in the semifinals and a similar score looked on the cards.
The Russian fought harder in a second set that went with serve until the 12th and final game.
Yet Pavlyuchenkova failed to earn a break point in the match and appeared outclassed. This was her first Premier-level final since Moscow in 2015.
She needed three sets to win all four of her matches en route to the final. Her semifinal opponent, Angelique Kerber, was the only seeded rival she faced before third-seeded Wozniacki.