The news comes as Rimes and married actor Eddie Cibrian -- long rumored to be dating -- have been photographed on various recent outings together.
Brandi Glanville, Cibrian's wife, said last week the actor filed for divorce at her request.
"After much thoughtful mutual consideration, Deane and I have agreed to move forward with dissolving our marriage," Rimes said in a statement on her Web site, referring to her husband, former backup dancer Dean Sheremet.
"This decision was amicable and we remain committed and caring friends with great admiration for one another. Thank you so much for all of your continued love and support -- it is deeply appreciated," Rimes said.