Ochoa turned in a 7-under 65 at the BosqueReal Country Club, creating an excellent chance that she can win in her native country for the first time.
"I didn't know about the record. But it is good to know," said Ochoa, whose best finish in this championship was a fifth in 2005. "Why not break it heading into the weekend?"
Her 65 tied the mark of Louise Friberg, who shot that score in the final round of last year's tournament en route to victory.
Na Yeon Choi was alone in second place at 67, followed by Brittany Lang, Pat Hurst and world No.2 Yani Tseng at 68.
"I cannot say it was a perfect round," Ochoa said. "I missed tee shots on the first two holes and I didn't hit a lot of greens."
Friberg opened defense of her title with an 81. Angela Stanford, the 2009 money leader on the LPGA Tour, is not entered this week.