He was found dead in a hotel in Palo Alto, California by a maid service on Friday.
According to his representative, John was recovering at the hotel after undergoing back surgery.
Police were called to the hotel for a report of a medical emergency, but he was pronounced dead on the scene, TMZ reported.
The coroner is investigating and cause of death is still unclear, but police do not suspect foul play.
Heard began his career in Hollywood in the late 1970s, with his first role in 'Chilly Scenes of Winter" followed by "Heart Beat" and "Cutter's Way", which has become a classic in recent years.
However, Heard is best known for starring in "The Sopranos" and playing Macaulay Culkin's father Peter McCallister in 1990's "Home Alone" and again in the sequel, "Home Alone 2: Lost in New York", two years later.