Lee shot a bogey-free 6-under 66 to take a two-stroke lead over Ochoa and four others after the first round of the $1.4 million Sybase Classic on Thursday.
Future Hall of Famer Se Ri Pak, up-and-coming Brittany Lincicome, rookie Angela Park and Hye Jung Choi joined Ochoa at 68, a shot ahead of three others led by recent first-time winner Meaghan Francella.
'I've been close in the last few weeks, and this will be a nice week,' said Ochoa, who hasn't won since supplanting Annika Sorenstam as the top-ranked player last month. 'It's important to be in a good position and to give myself a chance on Sunday and hopefully it will happen.'
The 25-year-old Mexican star certainly played well enough to have the lead, overcoming an early double bogey with a run of birdies on both nines of the Upper Montclair Country Club, which has replaced Wykagyl Country Club as the Sybase site.
Heading to the par-3 eighth, Ochoa was 5 under and seemingly headed for the lead. However, she pulled her tee shot left on her 17th hole and couldn't get up and down.
Still, it appeared it would be good enough for a share of the lead, that is until Lee came up big in the afternoon pairings.
Lee, who led after the first two rounds of last week's Michelob Ultra Open and eventually finished third, had birdies ranging in length from 7 to 18 feet, capping her round with a 9-footer on the par-5 18th.
It was impressive performance after Lee was forced to skip practice Tuesday because she was sick and then was limited to seven holes Wednesday in the pro-am because of heavy rain.
However, she also was coming off a great week at Kingsmill in Virginia. Her opening-round 63 and her 36-hole total of 131 were season lows on the LPGA Tour.
'I got great opportunity to win but you know, I couldn't handle the last two, three holes,' said Lee, who had a final-round 74 in Virginia. 'But I learn from that how I'm going to play.'
The competition will be tough if the leaderboard stays the same.
Ochoa, the LPGA player of the year in 2006, has a win and seven top-10 finishes in nine events this year. Lincicome, who won the HSBC Women's World Match Play Championship in New Jersey last summer, won the Ginn Open last month. Pak, who won her fifth career major last year with the McDonald's LPGA Championship, hasn't finished worse than 13th in her last four events.
Francella of nearby Port Chester, N.Y., also has game. She beat Sorenstam in a playoff earlier this year.
Ochoa is the one to fear though. She had seven birdies, a double bogey and a bogey on an old-fashioned course that reminded her of the one she plays at home.
Starting on No. 10, she birdied the 11th from 5 feet. She ran into trouble on 408-yard 12th, hitting her second into wood chips on a green protected by water. She chipped over the green and then chipped into the rough on the other side en route to a double bogey.
Birdies of 4, 2 and 15 feet got her righted, and she added three more birdies on her second nine, including a tap-in on a par 5.
'The last two weeks in Tulsa and Kingsmill, that was my struggle that every time I make a birdie, then a made a bogey,' Ochoa said. 'I felt like I couldn't get a good momentum going. That was the difference today.'
Lincicome had a wild round that included four birdies, two eagles, two bogeys and a double bogey. She didn't know she was tied for the lead after the morning until she was asked to report to the media room.
Pak, who has to complete four events to qualify for the Hall of Fame, was at even par after 13 holes. She birdied four hole of her final holes, with putts from a tap-in to 10 feet.
'I'm happy the way I finished but it's still three more days to go,' Pak said.
Park, an 18-year-old South Korean who was born in Brazil, had four birdies and no bogeys. She leads the tour rookie standing with three top-20 finishes, including a tie for third.
Choi had five birdies and a bogey. The second-year LPGA player has four top-25 finishes and four other events she would like to forget about.