Tseng, who has won three of the first six tournaments so far this season, shot 3-under-par 69 on Wednesday to share the lead with Brittany Lang and Jiyai Shin.
The 23-year-old Tseng, who has 15 international wins since January 2011, shot 4-under-par 32 on the front nine.
Lang would have had the solo lead but she made bogey on the 18th hole.
Morgan Pressell had 72, Lexi Thompson 75 and Hawaii native Michelle Wie 78.
LPGA commissioner Mike Whan said the unusual Wednesday start and Saturday finish for this tournament had to do with television and the fact the event is in Hawaii.
“This tournament, probably more than any other tournament we will play all year, is really going to be carried live all around the world,” he said.
“So, the interesting thing, for Lotte and its businesses throughout Asia, this will be a Sunday morning live finish. In America, it will be a Saturday night, primetime finish. So we really get interesting live TV all across the world. It’s one of the benefits of playing in Hawaii.”