Shin had three straight birdies on the front nine and added two more after the turn, offsetting a bogey at No. 9. She won at Kintetsu Kashikojima Country Club in 2010 and 2008.
''I'm glad I was able to play well in such tough conditions,'' Shin said. ''The wind really made it tough to drive, but I was able to make up for that with my approach shots and putting. It was a good start and I only had one bogey, hopefully the last one for the week.''
Uehara bogeyed the 10th, but then birdied the next three holes to add to birdies on Nos. 4 and 8.
Angela Stanford and defending champion Momoko Ueda of Japan were tied for third at 3 under in a group of six that also included Maiko Wakabayashi of Japan, Shanshan Feng of China, Na Yeon Choi of South Korea and Beatriz Recari of Spain.
Ueda, who also won here in 2007, is bidding to become the first Japanese to win back-to-back titles in the event's 40-year history.
''I really feel like this course suits my game,'' said Ueda, who birdied the last hole. ''If I can keep my nerves in check I can play well here and get a good result.''
Inbee Park shot a 70 and was among 10 players tied for ninth. The South Korean opened the LPGA Tour's Asian swing with a victory in Malaysia and finished second last week in Taiwan.
Park, who is looking to move ahead of American Stacy Lewis for the points-based LPGA Player of the Year award, struggled with the windy conditions and offset three bogeys with five birdies.
Top-ranked Yani Tseng and Lewis were among a large group tied for 19th after 71s.
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