Overnight leader Ueda, who won this tournament in 2007, sealed the win with a 15-foot birdie putt on the par-4 18th at the Kintetsu Kashikojima Country Club.
The 25-year-old Ueda earned $180,000 in the $1.2 million event. The victory was her first since the 2009 AXA Ladies Open and her second on the LPGA Tour and ninth on the Japan LPGA.
“I was starting to think I’d never win again,” said Ueda, whose Mizuno Classic win in 2007 earned her LPGA membership in 2008. “It’s been a tough four years in America.”
Feng shot a 7-under 65 in the final round to pull even with Ueda, who had a 69 as both players finished regulation at 16-under 200.
Feng had a 15-foot putt on the 18th hole in regulation to take the lead, but couldn’t convert the birdie. Then Ueda, playing in the final group, also had a chance to seal the win in regulation, but left her 16-foot birdie putt 10 inches to the right of the hole.
“It was my first playoff ever in my life,” said Feng, who earned her second career runner-up finish on the LPGA Tour. “The third time we played that hole, she made a good putt to win and I feel happy for her. This was her week.”
South Korea’s Choi Na-yeon had a 64—the best round of the day—to finish a stroke out of the playoff.
The Mizuno Classic is co-sanctioned by the U.S. and Japan LPGA Tours.