She leads by one shot over Jane Crafter, Jenny Lidback and Kellee Booth, all of whom shot 66 on Day One at the Corning Country Club.
Deb Richard, Eva Dahllof and Vickie Odegard are two back after rounds of 67.
Head set the pace early, carding seven birdies ' including five over her last seven holes ' against no bogies. For the remainder of the afternoon, her name sat atop the leaderboard, and no one could top it.
I am actually starting to play well now, commented Head following her round. I am striking the ball better and putting is starting to get better as well because I haven't holed a putt for the last four weeks.
Playing on the American tour full-time for the first time in her career, the 28-year-old Head is looking for her second professional victory. In 1999, she won the Malaysian Open overseas, and then went on to record four top-15 finishes on the Ladies European Tour, including a fourth-place finish at the Australian Open.
Her 65 on Thursday represents her best round ever on the LPGA Tour.
Her second best came in the opening round of this years Kathy Ireland Championship Honoring Harvey Penick, when she shot 67.
However, Head then went on to shoot scores of 76-76-74 to finish 69th.
I was only one off the lead in Texas after the first round and then finished quite badly after that, said claimed.
But hopefully I have learned a lot from that and I can go into tomorrow feeling confident.
Full-field scores from the Corning Classic