An object of the present invention is to provide an electric screwdriver device having a function for determining that a correct tightening operation has been carried out when the tightening operation has taken a time longer than a reference time predetermined for the tightening operation, characterized in comprising a novel feature for determining the reference time. The electric screwdriver device of the present invention comprises a torque monitor (40, S4) for monitoring whether or not a load torque in carrying out the tightening by using the electric screwdriver 12 has reached the tightening completion torque, a timer (40, S1, S5) for measuring the time consumed from the starting of the tightening operation until the tightening torque has reached the tightening completion torque, as the tightening operation time, and a feature (40, S6-S10) for determining the reference time for a subsequent tightening operation based on a plurality of tightening operation time obtained from the timer in the tightening operations carried out for the predetermined number of screws.