The 66-year-old reportedly died by suicide in a New York jail.
Epstein was in custody awaiting trial for charges of sex trafficking.
Epstein had pleaded not guilty and was being held without bail.
Last month, he was found semi-conscious in his cell with injuries to his neck. He was treated at a nearby hospital, reports say, before being returned to his cell at New York's Metropolitan Correctional Center.
Epstein was accused of paying girls under the age of 18 to perform sex acts at his Manhattan and Florida mansions between 2002 and 2005.
He was arrested on 6 July after landing in New Jersey on his private jet.