Peng became the first Chinese player, male or female, to hold the world No. 1 ranking in doubles. Her Taiwanese partner, Hsieh Su-Wei, is ranked second in doubles. The pair raised their record in doubles finals together to 10-0 by winning the Doha title on Sunday.
"I think this is really amazing and a great moment for me," said the 28-year-old Peng. “This is a really special time."
Li, who won her second Grand Slam title at the 2014 Australian Open, reached a career-high ranking of No. 2 on Monday. However, she is still 5,690 points behind No. 1 Serena Williams.