Lincicome won this major championship three years ago with a dramatic eagle on the closing hole and she made it through a hot afternoon at the Mission Hills Country Club without a bogey.
Lewis is seeking her first LPGA Tour victory and she ended a round in first place for just the second time in her career. She led the U.S. Women's Open going into the final round in 2008 and closed with a 76 to finish five shots out of the top spot.
Sandra Gal, who recorded her first tour victory last week at the Kia Classic, shared third place with Mika Miyazato at 67.
Chie Arimura and Jane Park both had a 68 while two-time former Nabisco winner Karrie Webb was among those at 69.
World No. 1 Yani Tseng, who already has four victories this season, shot a 70.