It's the second time she's left the sport.
World number one Ash Barty has made the shock decision to retire from professional tennis at the age of 25.
The Australian, who is the defending Wimbledon and Australian Open ladies singles champion, made the announcement on her Instagram page.
Today is difficult and filled with emotion for me as I announce my retirement from tennis. I wasn’t sure how to share this news with you so I asked my good friend @caseydellacqua to help me. I am so thankful for everything this sport has given me and leave feeling proud and fulfilled. Thank you to everyone who has supported me along the way, I’ll always be grateful for the lifelong memories that we created together.
It is the second time she's walked away from the game after taking a sabbatical as a teenager.