Grantray-Lawrence Animation originally wanted to feature the Fantastic Four as a segment on The Marvel Super Heroes, but Marvel Comics declined to sell them the rights.

The series was conceived after Hanna-Barbera's agent Sy Fischer noticed his son reading a Fantastic Four comic book and asked if he'd like to see it as a Saturday morning cartoon.

After his son confirmed his interest, Fischer pitched the idea to Joseph Barbera, who read the comic himself and agreed it would work well as a cartoon; the two then contacted Stan Lee at Marvel Comics to negotiate the rights.

Stan Lee was initially optimistic about the show but later expressed dissatisfaction, feeling the comics were written for an older audience while the cartoon felt aimed at six-year-olds.

Lee tried to give input to producers Hanna-Barbera and Krantz Films (for the concurrent Spider-Man series) but gave up after realizing their main concern was pleasing sponsors rather than staying faithful to the source material.

Unlike Lee, Marvel's owners Martin Goodman and later Cadence Industries were satisfied with the series since they secured a percentage of the gross revenue from it through syndication.

David Perlmutter's Encyclopedia of American Animated Television Shows notes that Paul Frees' Brooklyn-accented performance as The Thing stood out among an unusually well-cast voice cast.

The show is briefly referenced in the Marvel Cinematic Universe film The Fantastic Four: First Steps (2025).