The invention provides a hydraulic screwup control device and method of a skin-pass mill. The control device comprises a hydraulic pump station and a hydraulic control valve stand, wherein the hydraulic pump station is provided with two high-pressure pumps and three medium-pressure pumps; the inlet sides of each high-pressure pump and each medium-pressure pump are connected in series with suction port pipelines through cut-off valves and vibration absorbing throats, and the outlet sides of each high-pressure pump and each medium-pressure pump are provided with one-way valves, overflowing valves, filters, cut-off valves and pressure relays; the hydraulic control valve stand comprises a screwup cylinder dynamic control adjusting loop, a screwup cylinder quick opening or closing control loop and a screwup cylinder rod port control loop; a high-pressure oil pipeline of the hydraulic control valve stand is connected to oil channels of the high-pressure pump stations to realize screwup cylinder dynamic control adjustment; a medium-pressure oil pipeline of the quick opening and closing loop of the hydraulic control valve stand is connected with the medium-pressure pump station to realize quick acting of a screwup cylinder. With the adoption of the device, one hydraulic pump can be saved; the energy consumption of the hydraulic pumps in working and the number of related hydraulic elements can be correspondingly decreased, so that the consumption of spare parts and the running cost of the skin-pass mill can be reduced.