LAST UPDATED: August 28, 2016. Info derived from imdb. Only specific roles 2014-on noted by name. All known cast members noted.
The Marvel Super Heroes (1966)
Bernard Cowan (Narrator, Melter, Odin, Mandarin, Captain Torrak, Morgan, Ringmaster, Sando): died in 1990.
Jack Creley (?): died in 2004.
Len Carlson (Loki, Quicksilver, Black Knight, The President): died in 2006.
Max Ferguson (Hulk, Happy Hogan): died in 2013.
Vita Linder (Lady Dorma): died in 1966.
Don Mason (?): died in 1980.
Claude Rae (?): died in 1995.
Henry Ramer (Lord Vashti, the Mandarin, Crimson Dynamo, Borok, Major Uberhart, Wolfgang, Dr. Doom): died in 2009.
John Vernon (Iron Man, Namor the Sub-Mariner, Major Glenn Talbot, Major Cory): died in 2005.
Chris Wiggins (Thor, Hawkeye, Kraven, Grey Gargoyle, Byrrah, Balder the Brave, Jack Frost, Molto, Professor X, Count Nefaria): last known acting role in 2011.
Carl Banas (Rick Jones, Bucky Barnes, Hawkeye, Attuma): last known acting role in 1997.
Len Birman (Hercules): last known acting role in 1993.
Peg Dixon (Lady Dorma, Jane Foster, Wasp, Pepper Potts, Betty Ross, Lorelei, Enchantress, Scarlet Witch, Black Widow, Sharon Carter, Peggy Carter, Celia Rawlings, Countess De La Spirosa, Hyppolita): last known acting role in 1972.
Gillie Fenwick (Baron Zemo, Radioactive Man, Leader, Batroc the Leaper, Space Phantom, Dr. Cedric Rawlings, Heimdall, Jack Frost, Mister Hyde, Sandu, Count Nefaria, Premiere Pouldu): died in 2006.
Tom Harvey (Giant Man, Swordsman, Iceman, Chameleon, Super Skrull): died in 2014.
Paul Kligman (Red Skull, General Thunderbolt Ross, Power Man, Mole Man, Warlord Krang, Metal Master, Senator Harrington Byrd): died in 1985.
Paul Soles (Bruce Banner, Happy Hogan, Hawkeye, Rick Jones): in The Second Time Around (2015); My 90-Year-Old Roommate (1 episode 2016) in post-production; as Self: Lost Heroes (2014).
Sandy Becker (Captain America): died in 1996.
Vernon Chapman (Super Adaptoid, Edwin Jarvis): died in 2008.
Ed McNamara (Titanium Man, Swordsman, Boomerang, Mad Thinker): died in 1986.
Vic Perrin (Cyclops): died in 1989.
Arthur Pierce (Captain America): last known acting roles in 1989.
Len Carlson (Quicksilver): died in 2006.
Fantastic Four (1967-1968)
Paul Frees (Thing, Watcher): died in 1986.
Gerald Mohr (Mister Fantastic): died in 1968.
Jack DeLeon (Human Torch, Mole Man): died in 2006.
Jo Ann Pflug (Invisible Girl): last known acting role in 1997.
Joseph Sirola (Doctor Doom): last known acting role in 2010 but Codger (2013) completed.
Marvin Miller (Super Skrull, King Toth): died in 1985.
Don Messick (Kurrgo, Skrull Leader): died in 1997.
Charles Spidar (Citizen): last known acting role in 1972.
Vic Perrin (Red Ghost, Silver Surfer, Demon): died in 1989.
Mike Road (Prince Triton, Rama-Tut): died in 2013.
Ted Cassidy (Galactus): died in 1979.
Henry Corden (Attuma, Molecule Man): died in 2005.
Janet Waldo (Dorma, Princess Perla): died in 2016.
Hal Smith (Judge, Klaw, Otto Von Lenz): died in 1994.
Rege Cordic (Diablo): died in 1999.
Tol Avery (Warlord Morat): died in 1973.
Ginny Tyler (Anelle): died in 2012.
Frank Gerstle (Blastaar): died in 1970.
Pal Soles (Spider-Man, second Vulture), Peg Dixon (Betty Brant, Miss Trouble), Bernard Cowan (Narrator, Dr. Matto Magneto, Plutonian Leader), Paul Kligman (J. Jonah Jameson), Tom Harvey (Scorpion, Dr. Banas, Electro, Sandman, Baron Von Rantenraven, Dr. Altantean, Dr. Stillwell, Master Vine 1, Mugs Riley), Len Carlson (Green Goblin, Parafino, Human Fly, Bolton, Captain Ned Stacy), Vernon Chapman (Doctor Octopus), Gillie Fenwick (Lizard, Vulture, Executioner of Paris), Max Ferguson (Fifth Avenue Phantom, Electro, Vego, Mister Vine, second Doctor Octopus), Ed McNamara (Rhino, Blackbeard, Vulcan, Executioner of Paris), Henry Ramer (Dr. Noah Boddy, Grandini the Mystic, Henry Smythe, Le), Chris Wiggins (Mysterio, Infanata, Ponce de Léon), Carl Banas (Kotep): see Marvel Super Heroes above.
Billie Mae Richards (Billy Connor, Paperboy): died in 2010.
Alfie Scopp (Artie, Moose, Stan Patterson): last known acting role in 1988.
Frank Perry (Captain, James Boothe): died in 2009.
Claude Rae (Mr. Sloat, Charles Cameo): died in 1995.
Jack Mather (Jesse James): died in 2006.
J. Frank Willis (Cyrus Flintridge III): no known subsequent acting roles; as Self in 1970.