To provide a torque control nut, a torque control method and a socket for a power wrench, dispensing with marking for torque controlled nut, and controlling torque cost-advantageously.

This torque control nut 1 is circular in periphery and the outer peripheral part is provided with an outward projecting part 2 for rotating engagement, whereby when it reaches predetermined fastening torque, the projecting part 2 is broken. In fastening the nut 1 and controlling the torque, preferably the socket 4 for the cost wrench is used. The socket is provided with a hole having a circular inner periphery smoothly fitted to the outer peripheral part of the nut 1, and the inner peripheral surface part surrounding the hole is provided with a recessed part 7 for rotating engagement, which is closely engaged with the projeting part 2 for rotating engagement of the nut 1 in the rotating direction.