Having been taken to three-sets in all of her previous three matches here en route to the final, Sharapova saved her best tennis until last to defeat the Chinese in straight sets.
She broke Li twice in the first, but the Chinese managed to reply with a break of her own before Sharapova used the first of her three set points to take the first set.
The 26-year-old World No 2 then turned up the heat in the second set, breaking Li twice, while holding her own serve without due concern and her aggressive style paid off as she wrapped up victory in just under 93 minutes.
“I knew this was going to be the toughest match of the week, so I am really pleased with the way things worked out,” said Sharapova, who had lost the previous meeting to Li in the semi-final of January’s Australian Open. She has played good tennis all week and I am really happy to have won here again,” she added.
Having beaten Lucie Safarova, Ana Ivanovic and Angelique Kerber on the way to the final, Sharapova is now undefeated at Stuttgart on her second appearance at the tournament. After seeing off Victoria Azarenka in last year’s final, Sharapova then went on to win her fourth Grand Slam Roland Garros title.