A V16 engine is a sixteen-cylinder piston engine where two banks of eight cylinders are arranged in a V configuration around a common crankshaft. V16 engines are less common than engines with fewer cylinders, such as V8 and V12 engines. Each bank of a V16 engine can be thought of as a straight-eight, a design that can be inherently balanced. Most V16 engines have a 45° bank angle.

The Cadillac Sixteen is a concept car first developed and presented by Cadillac in 2003.