"We have a high level of concern. How could we not?", CBS entertainment president Nina Tassler told television journalists, responding to questions about persistent reports of drinking and partying by Sheen.
"On a basic human level, there is concern that this man is a father, he has children, he has a family. But you can't look at it simplistically. Charlie is a professional, he comes to work, he does his job extremely well. It is very complicated," Tassler said.
Tassler suggested that "Two and a Half Men" would remain on the network's schedule, at least for the time being.
"On a professional level, he does his job, he does it well. The show is a hit, and that's all I have to say," Tassler said.
"He certainly knows how we feel, and he knows the level of concern we have. But right now the show continues to be as successful as it always is. Everybody is doing their job and things are continuing as planned," she said.
"Two and a Half Men" is the top-rated comedy on U.S. television with an average weekly audience of some 15 million viewers. The show has helped CBS reign as the most-watched network in the United States for the seven years.
Sheen, 45, who plays a womanizing bachelor on the comedy, is the industry's highest-paid star with a reported salary of $1.8 million an episode.
But he has made numerous headlines in recent months after a conviction last year for attacking his then, third wife in Aspen, Colorado. Police said he drew a knife and threatened to have her killed. In August, a judge ordered him to spend 30 days in drug and alcohol rehab and placed him on probation.
In October, he was briefly hospitalized in New York when police found him acting drunk and incoherent in his room. His spokesman said at the time he had a bad allergic reaction to medication, but media reports said he had trashed his hotel room. A woman, later determined to be a porn star, had locked herself naked in the hotel room's bathroom and called for help to escape his rage.
This weekend, celebrity website TMZ.com reported that Sheen was in Las Vegas and again partying hard with more women.
He came close to being late for rehearsals after his Las Vegas weekend, triggering still more reports that producers may be considering possibly shutting down "Two and a Half Men" or persuading Sheen to return to rehab.
Tassler said she had "tremendous trust and respect" for the way that Warner Bros. -- the studio that produces the comedy which airs on CBS -- is handling the Sheen situation. Sheen signed up in May 2010 for two more seasons of the show.
Sheen is the son of "West Wing" actor Martin Sheen. He has five children from three marriages and other relationships.