An electrical wrench includes a housing, a power member, a reversing mechanism, a support transmission assembly, an opening gear, a main control assembly and a restoring assembly. The housing includes having two projections, for example shaped as claws, arranged oppositely to cooperatively define an entrance. The power member, the reversing mechanism, the support transmission assembly and the opening gear are cooperatively coupled to one another and accommodated in the housing. The opening gear includes an outer teeth portion, an opening and a driving portion in communication with the opening, a tubular member for engaging with a fastener positioned in cooperation with the opening gear through the entrance. The restoring assembly includes an identifying portion, a sensor for sensing the position of the identifying portion, a control circuit board, a restoring switch and a restoring switch operator.