Noren, a local favorite, had five birdies on the front nine en route to a bogey-free round and a 36-hole total of 11-under 133.
Shiv Kapur, who tied Noren's record at the Bro Hof Slott Golf Club about an hour after Noren finished, moved into second place at 8-under 136. Bubba Watson, who shot 5-under 67, and Jaco Van Zyl, with a 1-under 71, are tied for third at 6-under.
Scott Hend, Robert Karlsson and Anthony Wall, who each shot 70, are tied for fifth at 5-under.
Amateur Robert Karlsson, no relation to the professional in fifth place, started the day tied with Noren and Van Zyl for first but dropped back with a 3-over 75.
Noren's round Thursday was marred with a double bogey and a bogey but he had no negatives on his card Friday.
He started the day with birdies at Nos. 1 and 2, had two more at 6 and 7 and made the turn after a birdie at No. 9. His final birdie came at the 11th hole.