Creamer, who is looking for her first win of the season, leads after one round for the first time in her brief two-year career on the LPGA Tour.
Ochoa, who is trying to capture Player of the Year honors, shares second place with Joo Mi Kim and Liselotte Neumann at 6-under-par 66. Marisa Baena, Juli Inkster and Patricia Meunier-Lebouc are one stroke further back at minus-5.
Thursday's round was played under lift, clean and place rules after heavy rain soaked the course earlier in the week.
Creamer jumped out of the gate by sinking a 15-footer for birdie on the first. After a pair of pars, she two-putted for birdie at the par-5 fourth. Creamer again took advantage of a par-5 with a birdie on the sixth.
The 20-year-old, who won two times in 2005, rolled in her fourth birdie putt on the eighth at Magnolia Grove Crossings Course, which is part of the Robert Trent Jones Trail.
Creamer moved to minus-5 when her 6-foot birdie putt at the 10th found the bottom of the cup. She grabbed a share of the lead with a birdie on 12. Creamer remained there with pars on the next two holes.
At the par-4 15th, Creamer sank a birdie putt to take the lead. She made it two in a row with a two-putt birdie at the 16th. Creamer closed a bogey-free round with consecutive pars.
'I hit the ball really well, tee to green I played great,' said Creamer. 'I gave myself a lot of chances out there for birdies, and I missed a lot, but at the end of the day I played really solid and I'm very pleased with my first day.'
Ochoa leads Annika Sorenstam and Karrie Webb in the race for Player of the Year honors. Sorenstam (eight) and Webb (two) have combined to win 10 of the last 11 Player of the Year awards, but neither is in the field this week.
'No, no. I don't even think on that,' said Ochoa of winning on Sunday, which would lock up Player of the Year honors. 'You cannot be thinking of winning a tournament. It's only Thursday. I'm just trying to put myself in a good position for Sunday. And Sunday will be a different story depending on how the conditions are and how I am in the field.'
The 24-year-old Ochoa collected three birdies over her opening six holes. She parred her next four holes around the turn before tripping to a bogey at the par-4 11th.
Ochoa responded with a birdie run from there. She drained a 10-foot birdie putt on the par-4 12th and came right back to birdie 13. Ochoa continued to make birdies as her 7-foot birdie putt on 14 fell into the cup.
The Mexican made it four straight with a birdie on 15 from 9 feet out. She closed with three consecutive pars to finish two back.
'I think it was an easy front nine,' Ochoa admitted. 'I made a couple of birdies, especially on the par-5s. I think it's important to birdie the par-5. I think the key today was the good adjustment of clubs and the good distance control with my irons.'
Kim birdied the first to get her round going. She sank back-to-back birdies from the fifth, then holed out for eagle on the par-4 seventh to jump to minus-5. Her 8-iron from 151 yards dropped into the hole for the eagle.
The Korean parred the next five before making eagle on the par-5 13th to move to 7 under. After four pars, Kim three-putted for bogey at the last to share second.
Neumann was hot late on both nines. She was 1 under through six holes, then converted consecutive birdies from the seventh. Neumann got to minus-4 with a birdie at the 13th. She sank a birdie putt on 16 and made it two in a row with a birdie on 17 to finish at 6 under.
Stacy Prammanasudh, Sung Ah Yim and Jee Young Lee share eighth place at 4-under-par 68. Karen Stupples and Hilary Lunke, both former major champions, are among six players tied for 11th at minus-3.
Defending champion Christina Kim carded her lone birdie on the par-4 18th. That left her at 6-over-par 78, one stroke out of last place.