The Kindaichi Case Files mystery novels are written by Seimaru Amagi, who also writes the stories for the manga series of the same title. The illustrator and co-author is Fumiya Satō. As of April 20, 2001, 9 volumes have been published in Japan by Kodansha. A portion of the anime TV series episodes and the two animated films are based on the novels. All cases of Kindaichi featuring in the novels have been made into anime except for Heresy Mansion Murder Case, which is the final instalment of the novel series and the only instalment released after the conclusion of the anime television series. The 5th novel: Shanghai Mermaid Legend Murder Case, was also adapted into a live action movie.
The novel stories are somewhat connected with the stories in the original manga. For instance, Opera House, The New Murders in the novel series is a sequel to Opera House Murder Case in the manga series and Ghost Passenger Ship Murder Case in the novel series is a sequel to Lake Hiren Legend Murder case in the manga series. Some of the novels were translated to English and published in Japan.