The fifth-seeded defending champion, who had won the Thailand Open last week, defeated Li 13-21 22-20 21-19 in an hour and four minutes to lift her third title of the year.
"It was a really, really tough and I love the crowd here. It's really nice here. Whenever I enter the court, I feel like a champion here," said the world number five 22-year-old.
It was a battle of attrition for Saina against an opponent to whom she had lost four times and won just once -- that too way back in 2010 -- previously.
The start was ominous for Saina as she conceded four successive points.
The two players seemed engaged in a battle of smashes and were at par with each other when it came to baseline rallies.
But it was the netplay in which Li enjoyed the upperhand with her delicate winners that Saina found hard to counter in the opening game.
Li took an 11-6 lead with her seventh smash winner of the game leaving Saina with a lot of catching up to do. The Chinese girl's strategy was to engage Saina in aggressive baseline rallies before forcing her to commit errors from close range.
The exhaustion of a couple of hard-fought matches in the previous rounds also showed on Saina's on-court movement and her returns seemed sluggish.
The Indian could not breach the lead that Li had taken at the very start and although the Chinese floundered a bit in the middle of the game, Saina failed to capitalise and lost the opener in 15 minutes. In all, Li sent down 13 smash winners against Saina's eight.
Li's superior netplay clinched seven points for her while Saina settled for just four in the opening game. MORE