A hydraulic press is a hydraulic mechanism which is used for applying a large lifting or compressive force. It is the hydraulic equivalent of a mechanical lever. Hydraulic presses consist of a cylinder fitted with a sliding piston that exerts force upon a confined liquid, which, in turn, produces a compressive force upon a stationary anvil or base plate. The liquid is forced into the cylinder by a pump. The hydraulic press is now used widely in industries to form metals and for other tasks where a large force is required. They are manufactured in a wide variety of styles and sizes and in capacities ranging from 1 ton or less to 10,000 tons or more. Hydraulic presses are the most commonly-used and efficient form of modern press.

Hydraulic presses depend on the pressure flowing throughout a closed system to be constant. At one end of the system, there is a piston with a small cross-sectional area which is driven by a lever that will increase the force. Small-diameter tubing leads to the other end of the system.