The pair met when they were partnered together on U.S. TV talent series Dancing With The Stars in spring 2008.
In matching statements, released via blogging website Twitter.com, the couple announced their decision to part ways after just over a year.
Hough's message read, "Hi everyone, we wanted you all to know directly from us, that Shannon & I have decided to end our relationship as boyfriend & girlfriend.
The actress' note concluded, "However, we love & care about each other very much & will remain friends & in each other's lives.".