Neill first played Lois Lane in two black-and-white film serials, 1948's "Superman" and 1950's "Atom Man vs. Superman." She returned to the role in the second season of the "Adventures of Superman" 1950s TV series, which starred George Reeves, and stayed with the show until it ended in 1958.
Following "Adventures of Superman," Neill's onscreen appearances were limited, although she made cameos in many Superman-related live-action productions. She appeared in 1978's "Superman" as Lois Lane's mother, Ella lane, guest starred on the "Superboy" TV series in 1991, and played Gertrude Vanderworth, Lex Luthor's elderly, wealthy wife, in 2006's "Superman Returns."
The news of Neill's death was first shared on Facebook by her manager and biographer Larry Ward, who reported she passed away at her home in Tucson, Arizona, following a long illness.
"I found Noel to be generous with her time and the same person off the screen as she appeared to be on the screen," Ward wrote. "Her stamina was legendary as she happily made personal appearances and attended book signings well into her 90th year. She was kind, selfless, hardworking, funny with a quick wit, and assertive -- all the same qualities that embodied the character of Lois Lane."
Until recent years, Neill was an active presence on the comic book convention circuit. In 2010, a statue of Neill in character as Lois Lane was unveiled in Metropolis, Illinois.
According to Ward, Neill's funeral services will be private, and a public memorial is planned for later this year.