The present invention relates to a position learning system for an electric shift-by-wire system, which senses changes in the load of a motor according to operations of a four-stage detent plate and a detent spring to learn positions of shift stages of the electric shift-by-wire system, the position learning system including: a sensor for sensing the current generated from the motor; and a controller for receiving current data until a shift stage P is switched to a shift stage D or the shift stage D is switched to the shift stage P from the sensor, learning positions of shift stages R and N through the received current data, and performing offset operations on the basis of the learned positions of the shift stages R and N to learn positions of the shift stages P and D.