The Mansion of Innsmouth is an Action game, developed by Betop and published by I'Max, which was released in Japan in 1995. Loosely based on the H.P Lovecraft novel "The Shadow over Innsmouth".

On the cover and in the manual, the name is incorrectly rendered as "Insmouse".

In 2026, the game was announced to be part of Nintendo Classics - Virtual Boy, under the new localized title.

Set in the 1920's, a private detective is tasked with entering a mansion within a haunted forest in order to retrieve the Necronomicon and escape.