Claire Liu (born May 25, 2000) is an American professional tennis player. She reached her career-high singles ranking of world No. 52 in January 2023. Liu has won two singles titles and one doubles title on the WTA Challenger Tour.
On the ITF Women's Circuit she has won eight titles in singles and one in doubles.
In 2017, she was the world No. 1 in the junior rankings, winning the Wimbledon girls' singles title and finishing runner-up at the French Open. Liu also won a junior Grand Slam doubles title at Wimbledon with Usue Arconada in 2016.
Liu grew up in Thousand Oaks, California. Both her parents are Chinese immigrants. In 2023, she began maintaining a blog that recounts her experiences on the professional tennis tour and personal life.
Liu won the Wimbledon junior doubles tournament in 2016 with fellow American Usue Maitane Arconada, defeating Mariam Bolkvadze and Caty McNally in the final. The following year, after losing the French Open junior final to Whitney Osuigwe, she won the Wimbledon singles title against Ann Li, making her the first American to win the event since Chanda Rubin in 1992. With this Grand Slam success, Liu rose to world No. 1 in the girls' junior rankings.
2015: First professional title, mixed doubles major debut
She won her first professional title in March 2015 at a clay-court tournament on the ITF Women's Circuit. At age 14, Liu was the youngest tennis player to win a professional tournament since Anna Kournikova in 1996.
On her debut at the US Open, Liu was granted a wildcard into the qualifying tournament, losing in the final round. Liu, alongside Taylor Fritz, was given a wildcard for the mixed-doubles draw; they were defeated in the first round.
2017–2021: First major match win, top 100
After securing two ITF tournament wins in 2017, Liu was granted again a wildcard into the qualifying for the US Open and earned a spot in the singles main draw of a Grand Slam championship for the first time. She was defeated in the first round by Duan Yingying.
Liu qualified for the main-draw at the 2018 Wimbledon Championships and won her first match at a major by defeating Ana Konjuh, before losing in the second round to 11th seed eventual champion, Angelique Kerber, in three sets.
In October 2019, Liu won her fourth title on the ITF Circuit at a $25k tournament in Florence, South Carolina.
After finishing as a runner-up in two tournaments in 2020 and another two in 2021, Liu won consecutive tournaments in May 2021 at the $60k event in Charlottesville, Virginia and the $100k Charleston Pro Tennis. As a result, she entered the top 100 on 23 August 2021.
2022: First WTA Tour final and 125 title
In May, Liu won her first WTA 125 title at the Trophee Lagardère in Paris, defeating Beatriz Haddad Maia in the final. The following week she reached her first WTA Tour final in Rabat, losing to Martina Trevisan.
She made it through to the semifinals at the Jasmin Open in Monastir, Tunisia, defeating top seed Ons Jabeur in the quarterfinals for her first win over a top-10 ranked player. Her run was ended in the last four by fifth seed and eventual champion Elise Mertens.
2023: WTA 1000 third round, Challenger final
At the 2023 Australian Open, Liu overcame Madison Brengle to reach the second round, where she lost to 12th seed Belinda Bencic.