The 28-year-old world number 41 did not drop a shot in his eight-under-par 64 at the PGA West course in La Quinta.
Three Americans - 2013 US PGA champion Jason Dufner, Jerry Kelly and ex-US Ryder Cup player Jeff Overton - also hit 64s, one clear of the field.
Five-time major winner Phil Mickelson had an eagle in a 68 to lie four back.
In his first competitive round since October, Mickelson holed a 96-yard shot for eagle at the par four eighth and chipped in from just off the ninth green to return his lowest score at the La Quinta Country Club for a decade.
"I felt good with my game," said the 45-year-old, who recently began working with new swing coach Andrew Getson.
Lahiri, who last October became the first golfer from India to play at the Presidents Cup, has won twice on the European Tour.
His best PGA Tour finish came at last year's PGA Championship, when he was joint fifth.
Defending champion Bill Haas holed his second shot for an eagle at the par four first and posted a 66 to sit in an 11-way tie for seventh.
But England's former world number one Luke Donald had a level par 72 after mixing four birdies with four dropped shots.
India's Anirban Lahiri carded eight birdies to claim a four-way share of the lead after the opening round of the CareerBuilder Challenge in California.