solenoid valve s 1 and a second solenoid valve s 2 via a solenoid control valve 12 and to a primary pulley 16 as an operating pressure thereof and a fail safe valve 18 as a control pressure thereof via a speed ratio control valve 14 in addition a control pressure of the first solenoid valve s 1 is supplied to the speed ratio control valve 14 as a control pressure thereof and a control pressure of the second solenoid valve s 2 is supplied to the line regulator valve 4 and the second regulator valve 6 as control pressures thereof in addition a portion of the hydraulic pressure of the line regulator valve 4 is supplied to the second regulator valve 6 and is then secondly regulated the regulated hydraulic pressure is supplied to a pressure control valve 20 a damper clutch control valve 22 as a torque converter supply pressure and a reducing valve 24 the hydraulic pressure supplied to the reducing valve 24 is reduced and is then supplied to the third solenoid valve s 3 and the fourth solenoid valve s 4 as control pressures thereof the hydraulic pressure supplied to the pressure control valve 20 is controlled by the third solenoid valve s 3 and is then supplied to the manual valve 26 then selectively supplied to the forward clutch c or the.