An-Sophie Mestach (born 7 March 1994 in Ghent) is a Belgian tennis player.
Mestach has won six singles and one doubles title on the ITF tour in her career. On 5 January 2015, she reached her best singles ranking of world number 98. On 5 January 2015, she peaked at world number 399 in the doubles rankings.
Mestach won the junior events of the 2011 Australian Open in both singles and doubles. Following her wins in Melbourne, she became the number 1 ranked junior in the world. She won two Grade A and three Grade 1 tournaments in singles on the junior circuit.
In 2010, Mestach made her Fed Cup debut in a tie against Poland.
In 2012, Mestach won her first ITF singles title. She ended the year with a ranking of world number 361.
At the 2015 Australian Open, she made it to a Grand Slam main draw for the first time in her career, losing in the first round. After she had climbed up in the rankings at the end of the 2014 season, she did not have to go through qualifying.