Schwartzel, who started from the third hole at Centurion Club in a "shotgun start" in the controversial £20million, 54-hole event, fired six birdies and an eagle to top the leaderboard ahead of compatriot Hennie du Plessis.
The South African pair are both part of Stinger Golf Club in the team event, with another member, Branden Grace, in a tie for fifth on two under.
Former world number one Dustin Johnson and six-time major winner Phil Mickelson both shot one-under-par 69s to share seventh place with England's Sam Horsfield and Laurie Canter.
"I really enjoyed today," said Mickelson, who has not competed since February following the fallout from his explosive comments about the Saudi-back LIV Golf events and the PGA Tour.
"It was fun for me to get back out playing. I struck the ball really well and didn't putt very well.
"I really struggled with the putter the front, the first six, seven holes but I played really well and fought back after a double on nine to shoot one under and get myself right in it on the first day.
"With the short format it's important to have that good first day. I'm playing well and I feel like having my first competitive round now being back after a few months, I feel like I'm ready to relax and put it together and let it happen and not force it and really have a good round tomorrow."
The winner of the individual event will pocket $4million on Saturday, with the victorious team sharing $3million.