3D Monster Maze is a computer game developed from an idea by J.K.Greye and programmed by Malcolm Evans in 1981 for the Sinclair ZX81 platform with the 16 KB memory expansion. The game was initially released by J. K. Greye Software in early 1982 and re-released later the same year by Evans' own startup, New Generation Software. Rendered using low-resolution character block "graphics", it was one of the first 3D games for a home computer, and the first game incorporating typical elements of the genre that would later be termed survival horror.

3D Monster Maze puts the player in a maze with one exit and a hostile monster, the Tyrannosaurus rex. There, the player must traverse the maze, from the first-person perspective, and escape through the exit without being eaten.