Ochoa stands at 11-under-par 133 at the halfway point. Her total of 133 is a new 36-hole record at the event, snapping the old mark by two strokes. Juli Inkster first posted the old record of 135 in 1989 and later was matched by Brandie Burton in 1996 and Meg Mallon in 1999.
Karrie Webb, the 2000 champion, carded a 4-under 68 and shares third place at minus-6 with Seon-Hwa Lee (69).
Defending champion and three-time winner Annika Sorenstam could only shoot 72 on Friday. She stands at 1-under-par 143 and shares 12th place with 2004 Women's British Open champ Karen Stupples.
Sorenstam played the back nine first on Friday. She bogeyed the 13th, then the 17th for the second straight round to slide to plus-1. The Swede got one back with a birdie on No. 18.
Around the turn, Sorenstam birdied the second for the second day in a row. She birdied the fourth to get to 2 under for the tournament. After falling to even par with bogeys on seven and eight, Sorenstam birdied the ninth, her last, to finish at 1-under par.
Ochoa, who set a new course record on Thursday with her 62, parred her first four holes on Friday. She dropped in her first birdie on the par-5 third to get to 11 under.
The three-time winner on the LPGA Tour gave one stroke back to par with a bogey at the par-4 seventh. That was her first bogey of the event.
Ochoa parred her next three around the turn before converting a birdie effort on the par-5 11th from 8 feet out. She made it two straight as her birdie putt from 12 feet out on the 12th found the bottom of the cup.
She parred her next three holes before faltering to a bogey on the par-4 16th. Ochoa closed with two pars to remain four clear of Wie.
'I played really good today. I felt I played good,' said Ochoa. 'It was harder today than it was yesterday. I only was one under today. It's just the way it goes. The weather, it was very windy on the back nine. It was hard. So I'm really pleased with my one under.'
Ochoa leads after two rounds for the sixth time in her LPGA Tour career. She went on to win two of those events and finished second three other times.
'I really like my position,' Ochoa commented. 'And like I said, I'm going to take one day at a time and just come back tomorrow and enjoy a couple of more days.'
Wie played the back nine first on Friday and played her first six holes at plus one, with a bogey on the par-4 13th. She recovered that stroke with a birdie on the 16th to get to minus-6.
The young Hawaiian parred three straight around the turn. Wie birdied the second, but gave that stroke right back with a bogey on No. 3. The 16-year-old then birdied the fourth to get back to minus-7. Wie parred her final five holes to remain there.
Paula Creamer carded her own 1-under 71 to move to 4-under-par 140. She shares fifth place with Stacy Prammanasudh (73). Shi Hyun Ahn and amateur Angela Park are one stroke further back at minus-3. Carin Koch was joined in ninth place at 2-under-par 142 by 1993 winner Helen Alfredsson and Inkster, a two-time champion.
The cut line fell at 6-over-par 150 with 70 players moving on to the final two rounds. Among those missing out on the weekend are Kelly Robbins (151), Rosie Jones (153), Catriona Matthew (156) and Laura Davies (159).