Sania jumped from 11th spot despite not playing any event this week. The 26-year-old moved up as a result of other players dropping points.
Sania had won back-to-back titles as she lifted the China Open trophy earlier this month, followed by another triumph in Pan Pacific Open in Tokyo.
Her partner Cara Black of Zimbabwe too gained a position to be at number 13.
Italians Sara Errani and Roberta Vinci hold on to the joint number one ranking, while Su-Wei Hseih climbed two spots to number four and Katrina Srebotnik moved one spot higher to number three.