A wedge cam brake executes a braking operation by causing proximal end portions of brake arms to press a pair of pad assemblies against both sides of a brake rotor so as to hold it therebetween by means of a cam action of a wedge cam which is caused to move to a braking position along the direction of a rotational axis of a ball screw which is screwed into a ball nut which is provided integrally with the wedge cam as a result of the ball screw being driven to rotate. The wedge cam includes a compression coil spring for pushing to bias the ball nut towards the braking position where the proximal end portions of the brake arms are expanded and a spring holding mechanism for holding the compression coil spring in a biasing force accumulating state.