10:05 AM PT -- Busch just released a statement on the matter ... saying, "I am heartbroken to confirm that my wife Ashley and I are working to dissolve our marriage. Divorce is a personal and private matter and I hope our privacy will be respected."
Kurt Busch's wife has filed for divorce from the NASCAR star ... saying in court documents, obtained by TMZ Sports, their marriage is "irretrievably broken."
Ashley Busch filed the docs in Florida on May 9 ... and in them, she alleged Kurt "committed a tortious act." She did not expound on the allegation.
Kurt and Ashley -- a polo player -- first met in 2015 ... and later got married in December 2016, Ashley said.