The 26-year-old South African moved to a two-round total of 8-under 132 after sinking eight birdies with no bogeys in the European Tour and Asian Tour event at the Hong Kong Golf Club.
My iron shots were much better today and I got it closer, which made it easier to make the birdies, Oosthuizen said, adding that hes worked on his putting.
Wilson and Plaphol matched their 66s of the first round to stay even with Oosthuizen.
The 28-year-old Wilson has been on the cusp of success, shining in Ryder Cup play and notching eight second-place finishes on the European Tour. He lost a playoff against No. 2-ranked Sergio Garcia at the HSBC Champions two weeks ago.
Im on track. I feel like everything is moving forward, and one or two wins on my C.V. and I would feel pretty comfortable that everything is exactly where I want it, Wilson said.
Wilsons compatriot Fisher shot a second-round 65. The 20-year-old became familiar with the Hong Kong course by playing here as part of Nick Faldos junior competition series.
Faldo himself, a six-time major champion, shot a 70 Friday to finish at 2 over, missing the cut which was set at even par.
Veteran Scot Colin Montgomerie shot a 65 and is one shot behind the co-leaders in fifth place, along with Italys Francesco Molinari (67), Swedens Johan Edfors (65), Australias Marcus Fraser (66) and South African Richard Sterne (69).
Sterne was co-leader after the first round with Chinas Liang Wen-chong, who was two strokes further back after a 71 on Friday.
The 45-year-old Montgomerie said he is well suited by shorter courses like Hong Kong that value accuracy over power, compared to these American-style bombers-type courses that we tend to play a lot of.
Pleased to be on the leaderboard, the eight-time European Tour Order of Merit winner said its been too long, and its nice to see it there.
Lurking in the background at 5 under are two-time major winners John Daly and Bernhard Langer.
Langer, a two-time U.S. Masters champion, shot a 67 while Daly finished with his second consecutive 68 to qualify for what are becoming increasingly rare weekend appearances.
Defending champion Miguel Angel Jimenez and South African Rory Sabbatini just made the cut after shooting 69s in the 50th edition of the Hong Kong event.
Fresh from a win in Singapore that made him the first player to top $1 million in earnings on the Asian Tour in one season, Indian Jeev Milkha Singh also had an impressive round, shooting a 63 to move to tie for tenth place.
Former U.S. Open champion Michael Campbell dropped out before the second round with a lingering right shoulder injury.