Sheen showed little emotion and said nothing during his brief arraignment in Pitkin County District Court. The plea was entered by Richard Cummins, a Colorado attorney who represents Sheen.
No new details emerged about the Dec. 25 incident.
The star of "Two and a Half Men" on CBS is charged with menacing, criminal mischief and assault. Menacing, the most serious charge, carries a possible sentence of one to three years in prison.
A judge scheduled a jury trial for July 21.
Sheen is accused of assaulting Brooke Mueller Sheen at an Aspen home while they were on vacation. Charlie Sheen told police they were arguing but denied threatening to kill her.
In court, Sheen wore a black suit, white shirt and black tie. He chatted with a deputy and sipped water from a cup before the hearing started.
Afterward, he walked a few steps to the prosecution table and shook hands with Deputy District Attorney Arnold Mordkin.
Sheen, Cummins and attorney Steve Cochran of Los Angeles did not comment as they left the courtroom.
"I think the plea speaks for itself," Cummins later said by phone.
Stan Rosenfield, Sheen's agent, said, "Charlie is looking forward to the opportunity to clear his name."
It wasn't clear if a plea deal had been ruled out. Before the hearing, Mordkin said, "We always remain open. You never know."
Defense lawyers didn't address the issue.
Brooke Sheen told police her husband threatened her after she told him she wanted a divorce.
Sheen denied threatening his wife with a knife or choking her. He told officers they had slapped each other on the arms and that he had snapped two pairs of her eyeglasses in front of her, according to an arrest warrant affidavit.