Ochoa, from the nearby city of Guadalajara, fired a 9-under 64 on Friday to set a course record and take the lead after two rounds of the Corona Morelia Championship.
Spurred on by a cheering and supportive gallery, Ochoa had an eagle, eight birdies and one bogey in her second round. She stands at 11-under-par 135 for a three-shot lead over Sun Young Yoo.
Ochoa's 64 broke the previous Tres Marias course record of 66 set by Natalie Gulbis in the inaugural event last year. Her 135 is a tournament record for 36 holes, beating by two shots the previous record held by defending champion Carin Koch.
But the LPGA Tour's leading money winner was serious when she said she can do better.
'This is my best round in my country with my people,' Ochoa said. 'It was very special day and I will remember for many, many years. Right now, I believe I can do better.'
Friday's round will be a tough one to beat.
Ochoa had two early birdies at the first and second holes, but her round really took off when she holed an 8-iron from 131 yards for an eagle at the par-4 seventh.
Not nearly content, Ochoa birdied four straight holes after that. She drained 2-foot putts at the eighth and ninth, two-putted from 30 feet at the 10th and rolled in a 13-footer at the 11th.
She got to 11 under with another birdie at the par-3 14th, where she made a 10-foot putt.
'It's one of the things I've been working on with my coach -- when you start making birdies just to keep making them,' Ochoa said. 'I was hitting good shots and making putts. It was just one of those days when things are easy.'
Ochoa dipped to 10 under when she bogeyed 15 from the sand, but she got the shot back with a 15-foot birdie putt at the 18th.
Feeling no relief, even with a three-shot lead, Ochoa has the weekend to improve upon her 16th place finish last year.
'We still have two more days to go, but I like my position,' Ochoa said. 'I'm feeling good. It was a great day today and hopefully I'll play good the next two days and I will be in good shape.'
Yoo had a 6-under 67 on the par-73 layout to get to 8-under 138. She played bogey-free on Friday and has made just one bogey so far in 36 holes.
Kelli Kuehne shot a 3-under 70 and is alone in third place at 7-under 139. Julieta Granada and Heather Young are one shot further back at 140 following their second consecutive rounds of 70.
The cut fell at 5-over 151 with 70 players moving on to the weekend.