A lock-up clutch of a torque converter comprises an input member formed by a front cover of the torque converter, which has an outer peripheral end fixed to a shell of a pump impeller of the torque converter, and covers a rear surface of a shell of a turbine opposite to the impeller; a clutch disk operable to be connected to an inner surface of the front cover and disposed between the front cover and the turbine; and an output part formed by a plurality of output members which are arranged in a circumferential direction of the torque converter, seated on the rear surface of the turbine shell, positioned thereto by convex and concave portions, which are formed thereat and fitted together, and fixed together by fixing means.