Gloria McMillan is the last surviving cast member from “Our Miss Brooks”. Roy Thinnes from the 60s tv show “The Invaders” is also still alive
And Lisa Gerritsen, who played Phyllis’ daughter Bess.
I think Barbara Eden is the last survivor of “I Dream of Jeannie”.
You are correct. Based on what I see in IMDB, all of the other recurring cast members (i.e., there were seven actors who were credited as appearing in 20+ episodes) are deceased.
I believe the actress who played Jeannie’s sister is still alive.
My dad was 63 when I was born. He was born in 1904.
Are you the last remaining cast member of your life?
That is true. 
Dunno if its been said in the thread, but the cast members of Star Trek TOS must have a deal with the devil. FOUR out of 8 (if we count Majel) live??
Holy crap! Shatner’s 90?
Of the four, Shatner and Takei (particularly the latter) seem to still be in reasonably good health.
Walter Koenig (a relatively young 84) still does a little acting, and a few convention appearances, but my wife met him at DragonCon about five years ago, and she said that, at that time, he came across as being noticeably frail.
Nichelle Nichols was diagnosed with dementia some years ago, which eventually led to the end of public appearances for her; she is apparently now the subject of a legal fight over her custodianship.
George Maharis, who just turned 93, is the last remaining cast member of Route 66. Martin Milner died in 2015; Glenn Corbett, who replaced Maharis in season 3, died in 1993.
Why are you counting Majel? She died in 2008.
I think he was applying her to the eight count, not the four count.
Ah, got it.
Looking at the regular cast of The Andy Griffith Show, I believe the only surviving members are Ron “Opie” Howard (age 67), Elinor “Ellie Walker” Donahue (age 84), and Betty “Thelma Lou” Lynn (who just turned 95!).
Ron’s younger brother Clint (age 62) also appeared in five episodes. According to Wikipedia, he played “Leon, a toddler in a cowboy outfit who wandered around Mayberry and silently offered people a bite of his sandwich, to which they would respond, ‘No thanks, Leon.’”
One I just noticed is The Americanization of Emily (1964). Julie Andrews is the only surviving member of the cast.
I’m rather certain “Oldest Movie with One Surviving Cast Member” goes to…
Son of Frankenstein (1939)
Donnie Dunagan was 5 years old when he appeared as Peter von Frankenstein, grandson of the original doctor. He actually plays an important part in the plot and is memorable for his scenes with Karloff after the Monster abducts him. And he’s memorable for his distinctive Southern accent in a movie populated by Brits.
In case there is some other surviving cast member of that particular film (doubtful) I would offer up Donnie Dunagan as well for his work on Bambi (1942) as the voice of the title character. I didn’t check the cast of this one either but I’m fairly certain they are all dead.
Donnie Dunagan is still with us and kicking at the age of 87. I’m 99% certain he wins this thread.
Wow, the voice of young Bambi went on to become the youngest ever Marine Corps drill instructor, serve three tours in Vietnam and receive a Bronze Star and three Purple Hears. That’s some career trajectory!
Love this quote from an article about him: “I was blessed to be in a leadership role for 25 years, either in counterintelligence or training troops,” Dunagan said, “and if these animals I was leading had ever found out about Bambi — as much affection as I had for it — they’d have ridden me out on a rail.”
Another James Garner one. I was watching Move Over, Darling (1963) yesterday. I checked and the only surviving cast member is John Astin.