Local favorites Jie Zheng and Shuai Peng and unseeded Camille Pin also scored quarterfinal wins Friday.
Zvonareva needed just 55 minutes to get past Karin Knapp, 6-1, 6-0. She won 70 percent of the points in the match -- and more than 80 percent of her service points -- and didn't face a break point.
All of the Friday matches were decided in straight sets with Pin's 6-3, 6-3 win over Arantxa Rus the closest of the four. Zheng, seeded third, defeated Tamira Paszek, 6-2, 6-1, and Peng, seeded fourth, took out Jill Craybas, 6-4, 6-1.
Zvonareva goes against Zheng in Saturday's semifinals. It will be their first meeting in a WTA event. The other semifinal has Pin playing Peng. Peng has won both times she played Pin but they haven't squared off since 2005.
Saturday's winners advance to the tile match Sunday with a first-place check of $28,000 at stake.
2014 amfAR Inspiration Gala [PHOTOS]
Julius Randle breaks leg during NBA debut