The Smith & Wesson Model 500 is a five-shot, double/single action large-caliber revolver produced by Smith & Wesson, firing the .500 S&W Magnum cartridge.

The Model 500 was built on the entirely new X-Frame, which was developed exclusively to handle the immense muzzle velocity and pressures generated by firing of the .500 Magnum cartridge. It is among the most powerful revolvers in the world since its original release in 2003, and is marketed as "the world's most powerful handgun" by the manufacturer.

The Model 500 can fire a bullet weighing 350 gr (22.7 g; 0.8 oz) at 1,975 feet per second (602 m/s) generating a muzzle energy of over 3,030 foot-pounds force (4.1 kJ), roughly twice that of the .50 Desert Eagle, and a momentum of 13.7 Newton seconds. Commercial loadings are available in bullet weights ranging from 275 gr to 700 gr. The Model 500 is capable of firing the shorter .500 S&W Special cartridge.

Instead of a traditional barrel, the S&W 500 uses a rifled tube inside a barrel shroud that is secured by tension from the front. This tensioning leads to stability, making barrels less expensive to produce and resulting in a more accurate revolver.