In a one-sided contest, the fourth seed Indo-American pair took an hour and 10 minutes to dispatch third seeded pair 6-3 6-2 in the final of the USD 637,400 clay court Premier event.
Sania had won Pattaya Open with Anastasia Rodionova and had ended runners-up at Dubai and Indian Wells with regular partner Elena Vesnina of Russia, early in the season.
It was for the second time that Sania played a final alongside Mattek on the Tour. In 2009, she had won Cincinnati Open with the American.
Sania and her partner converted as many as four breakpoints out of five possible chances while they saved two of the three, to win the match comfortably.
They did not have an ideal start as they suffered a blow straight away to fall to a 0-2 deficit in the first set. But Rosolska and Zhengduo failed to hold on to their advantage and dropped their serve in the fourth game to fall back at 2-2.
The Indo-American combo then capitalised on their rivals' errors and a break of serve in the eighth game helped them win the set, 6-3.
Sania and Mattek entered the second set high on confidence and won two successive breakpoints to race to a 4-0 lead.
The Polish-Chinese pair though held on their remaining serves but could not bridge the score deficit as Sania and Matter served out of the match comfortably.
The Indo-American duo delivered 60 per cent first serve on target and dropped just 10 points on it, winning 21 out of 31 points en route to victory.
