This is the first horror film work for screenwriter Wyllis Cooper (credited as Willis Cooper in this movie). He is also known for his work as a radio personality. Cooper writes only one other horror screenplay, The Phantom Creeps, which was also released in 1939.
Amongst the notable discrepancies between this film and the previous ones is the name given to the original Doctor Frankenstein. In the James Whale films, the doctor's name is Henry Frankenstein. The placard upon his coffin in this film reads Heinrich von Frankenstein.
This is the final film work for actor Tom Ricketts, who played a Burgher in this movie. Ricketts passed away on January 20th, 1939 at the age of 86 - only seven days after the theatrical release of Son of Frankenstein. It was his 207th film role.