The 20-year-old from Seoul, South Korea, had an 8-under 64 on the 6,327-yard, par-72 course at Columbia-Edgewater Country Club.
Christina Kim, a gregarious 22-year-old from Northern California, finished the sunny and warm first day at 6 under. After her round, she hugged everyone in her group, even her standard-bearer.
Jenna Daniels, who started from the 10th tee, went on a tear with nine birdies and was tied for the lead late in the day. But the six-year tour veteran double-bogeyed the final hole and finished 6-under.
South Korean Mi Hyun Kim was at 5 under.
Lee, who had Betty Boop club covers in her bag, eagled the par-5 No. 7 hole. She went on to hit birdies on the first seven holes of the back nine.
She hadn't expected the quality round, especially after she bogeyed the par-3 No. 2 hole.
'After the eagle I thought, OK, maybe this will turn around,' she said through a translator.
She had half a sandwich at the turn and went with fairway woods and rescue clubs for her birdie spree as temperatures zoomed toward the 90s. It was the first time she could recall getting seven straight.
'After the front nine I tried to play very aggressive,' she said. 'I thought it would help me.'
The course record is shared by Beth Daniel, who was 10 under after the first round in 2003, and Annika Sorenstam had a 10 under in the second round in 2002.
'It was fun to watch,' said Tina Barrett, who was in Lee's threesome. 'She just was on a roll.'
Lee's caddie, Travis Wilson, said he didn't offer much advice.
'After they start making birdies, you just shut up,' Wilson said.
Kim got into trouble on the par-4 No. 17 hole.
'When I hit that tree I was going, `Please hit that tree,'' she said. 'Either I'm hitting a tree or I'm hitting a maintenance shed.'
Sorenstam, who won in Portland in 2002 and 2003, was taking some time off after winning the Scandinavian TPC, the tournament she sponsors. Sorenstam also skipped last year's Safeway Classic.
The defending champion is South Korean Soo-Yun Kang, who won her first and only LPGA victory in Portland. Kang had a 7-over 79 on Friday.
Kang, who said she has been bothered by a neck injury, has not fared well this season. Her best finish was 24th at Hawaii.
Ashley Prange, who won a place in the tournament with her victory in The Golf Channel's 'The Big Break V: Hawaii,' shot a 6-over 78.
The former North Carolina player also won expenses to compete on the Futures Tour, where she has won twice. The top five money winners on that tour get to play on the LPGA Tour next season.
The field of 142 will be cut after Saturday's second round.
The Golf Channel will televise the Safeway Classic starting at 10 p.m. ET Friday.