The Williams sisters beat defending champions Roberta Vinci and Sara Errani 6-3, 6-1 to move two wins away from their 14th Grand Slam tournament title.
Their victory in Armstrong Stadium finished less than an hour after Americans Bob and Mike Bryan had their quest for the calendar Grand Slam halted next door in Arthur Ashe Stadium. The Bryans fell 3-6, 6-3, 6-4 to Leander Paes and Radek Stepanek.
Serena Williams, looking for back-to-back singles titles, plays her semifinal Friday against Li Na.
The sisters play their next doubles match against Andrea Hlavackova and Lucie Hradecka.