Reciprocating type High Pressure Pump utilises the large area of Air-drive piston directly connected to a small-area pumping piston to produce hydraulic power from available shop air. The High Pressure Pump is powered and controlled by compressed air supply and requires no electrical connections. The High Pressure Pump comes in compact size and has the ability to perform in any position. The Reciprocating type High Pressure Pump is suited for maintaining hydraulic pressure for prolonged periods without excessive heat generation and costly power consumption.