Allison Van Uytvanck, a baseliner whose favorite shot is serve, began playing at age five. The Belgian contested first WTA qualifying event at 2011 Brussels, reaching the second round (l. Wickmayer).
After reaching the quarterfinals in Brussels in 2012, she won WTA 125k event in Chinese Taipei in 2013. That year, she claimed also three singles titles and one doubles title on ITF Circuit, and she made Top 100 debut on November 11 (rose from No.129 to No.100).
In 2014, Hsieh completed the first Top 100 season after claiming the semifinals in Hong Kong (l. to Ka.Pliskova) and the quarterfinals in Florianopolis (l. to Muguruza).
Her career-best finish came in 2015, at No.42. That year, on October 26, she reached the career-high ranking at No.41. It was the result of three tour-level semifinals in Katowice (l. Schmiedlova), Seoul (l. Begu) and Luxembourg (l. Doi) and her maiden Grand Slam quarterfinal at Roland Garros. She became the first Belgian to reach this stage in Paris since Henin won the title in 2007. Apart from that run, she has three other Slam main draw win to her name: 2014 Wimbledon (d. Niculescu, l.
Cibulkova in 2r), 2017 Roland Garros (d. Osaka, l. A.Radwanska) and 2018 Roland Garros (d. Wallace).
Van Uytvanck won her 10th and 11th ITF singles titles in 2016, at $50k in Stockton (d. Pivovarova) and $50k in Las Vegas (d. Kenin), and advanced to one tour-level QF in 2016 at Québec City (l. eventual champion Dodin).
She finished 2017 at No.75, her third Top 100 season. The year was highlighted by lifting first WTA singles title at Québec City (d. Babos in F). Van Uytvanck also reached two ITF singles finals in 2017, at $100k in Ilkley (l. Rybarikova) and $100k in Poitiers (l. Buzarnescu).
In 2018, she won her second tour-level title at Budapest in February, dropping only one set in the final (d. Cibulkova).