Abstract: The position detector system for guided vehicles has a memory block which stores each journey, divided into sections identified by their theoretical parameters and in which the correction curves are stored; at least one recording unit sensitive to travel in a curve and a relative position recording unit, signals from which are sent to a control unit which using the signals, establishes the profile of variations of the actual parameters of the correction curves and carried out an adjustment based upon achievement of the minimum error in the profiles of coordinates obtained from the theoretical parameters and the actual parameters, determining the absolute real position of the vehicle. The system is especially suited for the railway rolling stock industry.