Variable valve lift system

The present invention relates to a variable valve lift system, the cam shaft; The high lift cam provided on the cam shaft; The low lift cam provided on the cam shaft; Valve-lift device comprising a first coupling section for coupling the high lift driven by a driven by a high lift cam body and said low lift cam and a low lift body the high lift body and the low lift body selectively; Valve is provided in one end of the low lift the body to be opened and closed by the low lift body; And supporting the adjuster housing, the other end of the low lift body mounted to the cylinder head, the air is provided to be slidable in the adjuster housing, fish Just unit for controlling the clearance of the valve, and the adjuster unit and the adjuster the hydraulic clearance adjusting unit comprises second coupling parts for selectively coupling the housing; And hydraulic pressure supply unit to selectively supply the hydraulic pressure to the first engagement portion and the second engaging portion; and a.