The last names of Bud Abbott and Lou Costello's characters, Bud Alexander and Lou Francis, are actually their real middle names.
The picture in Dr. Gray's laboratory of Griffin, the inventor of the invisibility serum, is a photo of Claude Rains, who played the title role in "The Invisible Man (1933)."
823 Maple Lane is the same house on the "Universal" back-lot as 1313 Mockingbird Lane, otherwise known as the Munster Mansion.
A reporter asks Lou Francis (Lou Costello) who he has fought in the past. Lou replies, "Chuck Lamont, Bud Grant". Charles Lamont is the film's director and John Grant (nicknamed Bud) is the screenwriter.
This was originally intended to be a straight sequel to The Invisible Man . After the huge grosses from "Abbott and Costello Meet Frankenstein (1948)," the script was rewritten to make it another thrill comedy with Bud Abbott and Lou Costello. As it happened, Abbott and Costello met an invisible man in the earlier film, too, but it was a different character.