The two have been a couple on and off since they met while working together on "The Last Song" in 2009, when Hemsworth was 19 and Cyrus 16. A pattern of breakups and reconciliations continued after they announced their engagement in May 2012.
Now, representatives of both say the engagement is off, People magazine reported.
The couple have not been seen together in public since early August when they attended the Los Angeles premier of Hemsworth's latest film, "Paranoia," the New York Daily News reported. He also stars in the upcoming "Hunger Games: Catching Fire."
Cyrus has been in Europe recently promoting her latest album, "Bangerz."