The news comes weeks after a woman claimed she had sex with Kutcher, who recently joined the cast of TV's "Two and a Half Men."
"It is with great sadness and a heavy heart that I have decided to end my six-year marriage to Ashton," Moore, 49, said in a statement issued to People.com Thursday.
"As a woman, a mother and a wife there are certain values and vows that I hold sacred, and it is in this spirit that I have chosen to move forward with my life. This is a trying time for me and my family, and so I would ask for the same compassion and privacy that you would give to anyone going through a similar situation."
"I will forever cherish the time I spent with Demi. Marriage is one of the most difficult things in the world and, unfortunately, sometimes they fail," Kutcher, 33, said in his own statement.