The New York-born star started his career on Broadway in Mrs Dally Has A Lover before being cast in Reflections In A Golden Eye opposite Elizabeth Taylor and Marlon Brando in 1967.
Over the course of his career, Forster starred in more than 100 films including Jackie Brown, Charlie's Angels: Full Throttle, The Descendants and Me, Myself and Irene.
His role in Jackie Brown even earned him an Oscar nomination in 1997.
Forster also appeared in dozens of TV shows, including Breaking Bad, Twin Peaks, Heroes and Last Man Standing.
Breaking Bad star Bryan Cranston was among the first to pay tribute to Forster in an emotional post on Twitter.
I’m saddened today by the news that Robert Forster has passed away. A lovely man and a consummate actor. I met him on the movie Alligator (pic) 40 years ago, and then again on BB. I never forgot how kind and generous he was to a young kid just starting out in Hollywood. RIP Bob. pic.twitter.com/HtunD0Fx6g
Ah, f..k. Robert Forster was among my favorite actors of any era. So good, so comfortable in his own leathery skin. Met him a few times. Always kind, huge @tcm fan. Kept dozens of wrapped letter openers in his trunk to give as gifts. Got one. Will watch Jackie Brown this weekend. https://t.co/KZq2RMvGHk
What a tremendous loss. RIP to the great Robert Forster. I love him in genre classics like VIGILANTE, ALLIGATOR, and of course JACKIE BROWN, but MEDIUM COOL is his my favorite of his roles; his most vital and fearless work. pic.twitter.com/cTwZ7XIPHd
He is survived by his four children Bobby, Elizabeth, Kate and Maeghan; his grandchildren Tess, Liam Jack and Olivia; and longtime partner Denise Grayson.