The deal apparently came together quickly, following reports earlier this week that negotiations with film actor Hugh Grant to join the show had fallen through.
Kutcher is familiar to television audiences through his role on Fox's "That 70s Show," film roles like the romantic comedy "No Strings Attached" and for producing and hosting the prank show "Punk'd."
Kutcher said he believes that "we can fill the stage with laughter that will echo in viewers' homes.
"I can't replace Charlie Sheen but I'm going to work my ass off to entertain the hell out of people," he said.
Kutcher's quote was the only mention of Sheen in the news release. Warner cut short the show's eighth season and fired Sheen two months ago following his public implosion through hard partying and angry criticism of show creator Chuck Lorre.
"We are so lucky to have someone as talented, joyful and just plain remarkable as Ashton joining our family," said Lorre, also the show's executive producer. "Added to that is the deep sigh of relief knowing that our family stays together. If I was any happier, it'd be illegal."
Producers did not immediately say how Kutcher would be integrated in a show where Sheen's character was the comic centre, portraying an advertising jingle writer with a playboy lifestyle not unlike the actor's own. Jon Cryer portrays Sheen's brother, and Angus T. Jones plays Cryer's son.
Even through reports of Sheen's personal problems, "Two and a Half Men" had continued to reign as television's top situation comedy and anchor CBS' Monday night lineup. A deadline on deciding whether the show would continue was looming with CBS set to unveil its autumn schedule to advertisers in New York next Wednesday.
