'Back to the Future' Star James Tolkan Dead at 94

James Tolkan, the actor best known for his work in the "Back to the Future" trilogy, has died, TMZ can confirm.

Bob Gale, who, along with director Robert Zemeckis, created the franchise, tells TMZ ... Tolkan died Friday, peacefully at his Lake Placid home. His cause of death was not revealed.

The beloved hard-nosed character actor appeared in several classic '80s films, such as "Top Gun" and "War Games" ... but he was best known as Vice Principal Strickland in the 'BTTF' films, always giving Marty McFly a hard time about being a slacker.

His agent, John Alcantar, tells TMZ ... James loved the 'BTTF' fandom and got a kick out of being at conventions. Despite playing hard-asses on screen ... Tolkan was a total sweetheart of a man.

He is survived by his wife, Parmelee.

Tolkan was 94.