The EMD GP18 is a 4-axle diesel-electric locomotive built by General Motors, Electro-Motive Division between December 1959 and November 1963.

[1] Power was provided by a 16-567D1 16-cylinder engine which generated 1,800 horsepower (1.34 MW).

350 examples of this locomotive model were built for American railroads, 40 units were built for Mexican railroads, 12 were built for export to a Brazilian railroad, 2 were exported to Peru, and 1 was exported to Saudi Arabia.

It was designed nearly identically to the two previous models, but differed in having a metal grid over its radiator shutters, while the GP7 and GP9 instead incorporated a design described as looking like "chicken wire".

GP18s could be customized by their buyers: railroads ordered GP18s with either high or low short hoods, with or without dynamic brakes, and in the case of Grand Trunk Western, with the optional addition of steam generators.