Sjoholm, looking for his first win on the tour, pulled together a round with four birdies and two bogeys in addition to eagles at the par-5 third and 16th holes. He's at 11-under 133 after 36 holes.
That's two strokes better than five players tied for second, including first-round co-leader Fabrizio Zanotti who had a 1-under 71 Friday. Thomas Norret, who shot 68 in the second round, is also at 9-under as are Paul McGinley, Danny Willett and Chris Wood, all with 70 in the second round.
Shiv Kapur (70) is alone in seventh at 8-under with five golfers tied for eighth at 7-under. Marcus Fraser, the other first-round co-leader, is among a large group at 6-under 138 after he posted a 2-over 74 Friday.
Sjoholm started on the second nine of the Gulf Club Gut Larchenhof on Friday and was 1-under through six holes. He had a 3 at the 577-yard 16th but gave those strokes back with bogeys at 17 and 18.
He had a birdie at the second hole before jumping up again with an eagle at the 546-yard third hole. Sjoholm pulled clear of the field with birdies at 5 and 9.