On March 20, 2006, Sheen stated that he questions the U.S. Government's account of the September 11 attacks.Sheen said during the interview that the collapse of the World Trade Center towers looked like a controlled demolition.
Sheen has since become a prominent advocate of the 9/11 Truth movement. On September 8, 2009, Sheen appealed to President Barack Obama to set up a new investigation into the attacks. Presenting his views as a transcript of a fictional encounter with Obama, he was characterized by the press as believing the 9/11 commission was a whitewash and that the administration of former President George W. Bush may have been responsible for the attacks

Sheen was the 2004 spokesperson for the Lee National Denim Day breast cancer fundraiser that raised millions of dollars for research and education regarding the disease. Sheen stated that a friend of his died from breast cancer, and he wanted to try to help find a cure for the disease.
A major donor and supporter of Aid For AIDS since 2006, Sheen was honored with an AFA Angel Award, one of only a few ever given, at the nonprofit's 25th Silver Anniversary Reception in 2009. In addition to his financial support, he has volunteered to act as a celebrity judge for several years for their annual fundraiser, Best In Drag Show, which raises around a quarter of a million dollars each year in Los Angeles for AIDS assistance. He has brought other celebrities to support the event, including his father, actor Martin Sheen. Sheen's interest in AIDS was first reported in 1987 with his support of Ryan White, an Indiana teenager who became a national spokesperson for AIDS awareness after being infected with AIDS through a blood transfusion for his hemophilia. Sheen is donating one dollar from each ticket sold from his “My Violent Torpedo of Truth/Defeat is Not An Option Show” 2011 tour to the Red Cross Japanese Earthquake Relief Fund.

On May 20, 1998, Sheen overdosed while using cocaine and was hospitalized. On August 11, 1998, Sheen, already on probation for a previous drug offense, had his probation extended for an extra year and entered a rehab clinic. In a 2004 interview, Sheen admitted that the overdose was caused by his experimentation with injecting cocaine.
In 2009, Sheen was arrested and released from jail after posting an $8,500 bond. Sheen was charged with felony menacing, as well as third-degree assault and criminal mischief. On August 2, Sheen pleaded guilty to misdemeanor assault as part of a plea bargain that included dismissal of the other charges against him. Sheen was sentenced to 30 days in a drug rehab center, 30 days of probation, and 36 hours of anger management.

Sheen has been married three times and has five children, including one with his former high school girlfriend, Paula Profit. In 1990, Sheen accidentally shot his then fiancee, Kelly Preston, in the arm. Preston broke off the engagement soon after.
In the 1990s, Sheen dated a number of adult film actresses, including Ginger Lynn and Heather Hunter.
On September 3, 1995, Sheen married Donna Peele.That same year, Sheen was named as one of the clients of an escort agency operated by Heidi Fleiss.
On June 15, 2002, two years after they met on the set of the movie Good Advice, Sheen married actress Denise Richards. They have two daughters, Sam Sheen and Lola. In March 2005, Richards filed for divorce, accusing Sheen of alcohol and drug abuse and threats of violence.The divorce was finalized in November 2006 and preceded a custody dispute over their two daughters.
On May 30, 2008, Sheen married Brooke Mueller, who later gave birth to their twin sons, Bob and Max. Sheen filed for divorce from Mueller in November 2010.
As of March 1, 2011, Sheen was concurrently living with pornographic actress Rachel Oberlin and model and graphic designer Natalie Kenly, whom he collectively nicknamed his "goddesses". Also as of March 1, police had removed Bob and Max from Sheen's home. Sheen told NBC's Today, "I stayed very calm and focused." This move came after, according to People, Mueller had obtained a restraining order. The document said, "I am very concerned that [Sheen] is currently insane." Asked if he would fight for the children, Sheen texted People, "Born ready. Winning."