He took the lead on TPC San Antonio's AT&T Canyons Course with a two-putt birdie after reaching the par-5 15th in two with a 3-wood. He parred out to remain one ahead.
Tom Pernice Jr. was a stroke back after a 66. He won the 3M Championship in August in Minnesota.
"My swing is continuing to improve, and this might have been the best I've driven the ball this year," Pernice said after missing just one fairway on the back nine. "It set me up for a lot of good opportunities."
Langer and Anders Forsbrand followed at 67, and Colin Montgomerie, Russ Cochran, Dick Mast and Bob Tway shot 68.
"''He's swinging really good," Langer said about Forsbrand, who was an assistant when Langer captained the winning 2004 European Ryder Cup team. "He's certainly hitting the ball as good as anyone on this tour right now."
Fred Couples, the 2011 winner who missed the event last year because of a back injury, had a quadruple-bogey 8 on the first hole en route to a 75.
David Frost, a playoff winner over Langer last year in the event, shot 77.