At 6-under 66, Ji joins Americans Pat Hurst and Brittany Lincicome at the top of the leaderboard through one round. The trio has a one-shot lead over American Christina Kim and South Koreans Jin Joo Hong and Kyeong Bae.
"Actually, all of my shots (were) very good," Ji said. "My putting was doing very good."
"I think there should be a lot of low scores," Kim said.
Two-time winner Annika Sorenstam mixed five birdies and four bogeys for a round of 1-under 71 to share 16th place with Laura Davies and Rachel Hetherington among others.