Conley's wife, Louise, said he had dementia.
According to The Hollywood Reporter, Conley starred in all nine seasons of the popular CBS series, which aired from 1971 to 1981. He also returned for all of the series' reunion movies.
Conley's "Walton's" co-star, Mary Beth McDonough, made the announcement in a post on her Facebook page.
"It is a a sad day. So sorry to let you know Joe Conley .our beloved Ike Godsey passed early this morning, please keep him, Louise, and his family in your prayers. RIP Mr. Godsey," McDonough wrote.
Conley is survived by his wife, Louise, and four children, Kevin, Julie, Erin and Jana.
A native of Buffalo, N.Y., Conley also appeared in "Mister Ed," "Lassie," "Green Acres" and later, "Castaway."