PURPOSE: A torque converter for a vehicle is provided to maximize cooling effect by arranging an oil circulation hole to pass through the center of a frictional material on a piston. CONSTITUTION: An impeller(6) is combined with a front cover and rotates. A turbine is arranged on a position facing the impeller and rotates according to the rotation of the impeller. A reactor(10) is located between the impeller and the turbine and changes the flow of oil from the turbine to the impeller. A lockup clutch is movably combined with the shaft of the turbine and includes a piston which is closely adhered to or separated from the front cover by the pressure of the oil. A torsional damper is combined with the lockup clutch and includes springs which are arranged in a circumferential direction of the shaft. A torsional damper includes a retaining plate which supports the springs. A frictional material is combined with a frictional material which is closely adhered to the front cover. An oil circulation hole which passes through the center of the frictional material is provided to the piston.
