Ryu So-yeon (Korean 유소연, RR Ryu So-yeon, MR Ryu Soyŏn, pronounced ; born 29 June 1990), also known as So Yeon Ryu, is a South Korean professional golfer who plays on the LPGA Tour and on the LPGA of Korea Tour. She is a two-time major winner having won the 2011 U.S. Women's Open and the 2017 ANA Inspiration. On 26 June 2017, she became just the 11th No. 1-ranked golfer in the Rolex Rankings by virtue of winning her 5th LPGA Tour title at the Walmart NW Arkansas Championship.
Ryu turned professional in 2007 at age 17. Her first win as a professional came in February 2008 on the American Cactus Tour, in which she won by six strokes. She then joined the LPGA of Korea, winning the first event she played, the Sports Seoul Open.
On 11 July 2011, Ryu won the U.S. Women's Open. On the 18th hole of the final round, the toughest hole for the tournament, she trailed the clubhouse leader Hee Kyung Seo by one stroke, but hit her approach to 6 feet and made the birdie putt to force a playoff. Ryu won the three-hole playoff with a birdie on the last hole.