Lifter is composed of a walking mechanism, a hydraulic mechanism, an electric control mechanism and a supporting mechanism. Hydraulic oil by the vane pump to form a certain pressure, the oil filter, flameproof type solenoid valve, throttle valve, liquid control one-way valve, balance valve in hydraulic cylinder is arranged at the lower end of the, the liquid cylinder piston upward movement, lifting a heavy object, the hydraulic cylinder is arranged at the upper end of the oil return the flameproof type electromagnetic reversing valve back to tank, the rated pressure through the relief valve adjustment, through the pressure table observe the pressure gauge readings.