World number four Massaro, 33, won 11-8 12-10 11-5 in 35 minutes to become the second woman to win the title twice, after Malaysia's Nicol David.
"I'm one of the oldest on Tour and as long as I feel I'm still in contention to win titles, I'm happy," she said.
Compatriot James Willstrop was beaten 12-10 11-9 11-8 by Egypt's Mohamed Elshorbagy in the men's final.
Former world number one Willstrop, who is now ranked sixth, said: "To make the final was a great pleasure. I was loving every minute, apart from losing.
"Full credit to him, he stopped me playing so there are no complaints."
England's Laura Massaro defeated world champion Nour El Sherbini to defend her Dubai World Series Finals title.