Shortly after 11 a.m., a woman called authorities to report that she had found the body of her friend just off the roadway and down a hillside in the 15500 block of Bandy Canyon Road.
A missing person's report was filed two weeks ago. The friend told FOX 5 he was last seen leaving a friend's house on Highland Valley Road at Cordiano Winery.
Signs of decay appeared to show that the body had been there for over a week, according to San Diego Sheriff's Department.
An investigator from the Medical Examiner's Office determined there were no obvious signs of trauma. California Highway Patrol and San Diego Sheriff's Department were also at the scene.
The man's name has not been released. The body was taken to the Medical Examiner's Office to determine the cause of death.