EVIAN, September 11, 2014 (AFP) - She led by four shots from Australia's seven-time major champion Karrie Webb and by five from compatriot Hur Mi Jung.
Kim's is the lowest ever round in a major golf championship - replacing the 62s of Finland's Minea Blomqvist at the 2004 Women's British Open, and Lorena Ochoa, at the 2006 Kraft Nabisco Championship. The lowest round in a men's major is 63.
It was a flawless effort, with Kim's putter like a magic wand in perfect sunny afternoon conditions in southeastern France.
Kim was out in 30 with birdies at the first, third, fourth, sixth and ninth and made more at the 11th, 13th, 14th, 16th and 18th in a homeward 31.
"I like hard courses and I played really well today," said Kim.
"I didn't come here with too high expectations. I just wanted to play well. I putted great today. My longest was about 45 feet at the 14th."
Kim has already been hailed as the best Korean golfer since Pak Se Ri, the player who sparked her country's revolution in the game with two major victories in her rookie 1998 season.
As an amateur in 2012, the youngster won the Lotte Mart Women's Open on the Korean LPGA Tour by nine shots and, months later, she claimed the Suntory Ladies' Open on the Japanese circuit.
On turning professional last year she claimed the China Ladies' Open and was the Korean LPGA Rookie of the Year.
Patience was the key for defending champion Suzann Pettersen. One over par after 13 holes she then reeled off five birdies in a row for a four under par 67.
"I just wanted to keep going," she said.
"I'm thrilled to finish with five straight birdies. The most positive aspect of the day was that I was patient enough to wait for something to happen and not flip out."
Pettersen started at the tenth and started with a bogey. She birdied the 15th and the second but also dropped more shots at the 16th and 3rd. Then came the spectacular finale.
"I hit a great iron shot into number five and that was the trigger," she continued. "The course was in great shape today but starting at the tenth is tough. It's not the most comfortable of tee shots."
Webb won the event in its pre-major guise as the Evian Masters in 2006 and the veteran showed she is still a force to be noticed.
The 39-year-old seven-time major champion had eight birdies in the near-perfect scoring conditions.
Webb started working with a new coach, Mike McGatrick, earlier this season and she has made some minor changes to her swing.
"But the difference today was my putting," she said. "I changed putter to one I used about 12 years ago and suddenly started holing a few."
Webb dropped a shot at the 18th. "But I was pretty solid tee to green today," she said. "And it was my best round for absolutely ages."
But it was a hugely disappointing day for US Women's Open Champion Michelle Wie. Playing in her first event for five weeks due to a hand injury, she pulled ut at five over par after 13 holes.
"It sucks," said the popular 24-year-old. "I wasn't 100% but really wanted to play. But I hit a stinger three wood shot at fourth hole and it really hurt. I hope this isn't my last event of 2014."
Leading first round scores on Thursday from the Evian Championship USLPGA golf tournament (* denotes amateur).
61 - Kim Hyo Joo (KOR)
65 - Karrie Webb (AUS)
66 - Hur Mi Jung (KOR)
67 - Brittany Lincicome (USA), Suzann Pettersen (NOR)
68 - Julieta Granada (PAR), Karine Icher (FRA), Mariajo Uribe (COL), Amy Yang (KOR), Dewi Claire Schreefel (NED), Sarah-Jane Smith (AUS)
69 - Chun In Gee (KOR), Moriya Jutanugarn (THA), Kim In Kyung (KOR), Mina Harigae (USA), Juli Inkster (USA), Lydia Ko (NZL), Mika Miyazato (JPN), Jaye Marie Green (USA), Emily Kristine Pedersen (DEN)*, Candie Kung (TAI), Lee Il Hee (KOR), Pak Se Ri (KOR), Paula Creamer (USA) Park Inbee (KOR), Lizette Salas (USA), Ayako Uehara (JPN)