Lee's score was good enough for a two-stroke lead over Carin Koch and reigning Women's British Open champion Jeong Jang, who both shot 5-under 67s at Nine Bridges Golf Club.
Hee Young Park, another LPGA of Korea player, is alone in fourth place at minus-3 after an opening-round 69. Behind her is a group of five golfers tied for fifth place at 2 under.
Two of the three previous winners of this event are in the field, but neither had a particularly good round. Defending champion Grace Park and 2003 winner Shi Hyun Ahn are tied for 18th place with 13 other players at 1-over 73.
Also coming in at 1-over 73 was Rookie of the Year Paula Creamer, who already has three wins outside the United States this year.
Annika Sorenstam, who leads Creamer at the top of the money list by more than $700,000, struggled to a 3-over 75 and is tied for 39th place with four other players.
Looking for her ninth win of the season, Sorenstam got off to a shaky start with four bogeys and just one birdie in her first round.
Everyone is looking up at Lee, who began her impressive round on the back nine with birdies on six of her first nine holes to reach minus-6 around the turn. She birdied No. 1 as well to reach 7 under, but quickly dropped two strokes with her only bogeys of the round at the second and third.
Lee rebounded with her eighth birdie at the par-4 fourth and strung together four consecutive pars before ending her round with a birdie at the ninth to reach 7 under again.
Along with 11 other LPGA of Korea players, Lee earned her invitation to the event by being among the top 12 on that circuit's points list. The remaining tournament births in this 69-player field went to 50 LPGA Tour players as well as one Japan LPGA player and six sponsor exemptions.
Tied for fifth place at minus-2 are Sherri Steinhauer, Ran Hong, Sun Hwa Lee, Mi Hyun Kim and Sophie Gustafson. Trailing that group by one stroke at 1-under 71 are Becky Morgan, Aree Song, Rachel Hetherington and LPGA of Korea player Hyun Hee Moon.