Method for the directional determination of an earth fault in an electric power distribution network, comprising the steps of: Determining a residual current phasor, Determining a residual voltage phasor, characterised in that it comprises the steps of: Determining an active current by projection of the residual current phasor on the residual voltage phasor, Determining of the residual voltage phasor module, Comparing the residual voltage phasor module with a threshold, and in that it comprises the following steps, as long as the residual voltage phasor module remains higher than the threshold or a fraction of the threshold, and for a predetermined number of iterations starting from the moment when the residual voltage phasor module is greater than the threshold: Determining (E9, E12) the integral of the active current and of the sign of the integral of the active current, Determining the residual current phasor module, Determining the number of times when the residual current phasor module is greater than a predetermined threshold, during the predetermined number of iterations, If the residual current phasor module is greater than the predetermined threshold at least one time, during the predetermined number of iterations, Determining the location upstream or downstream of the defect according to the number of times when the sign of the integral of the active current was positive or negative during the predetermined number of iterations. Determining a residual current phasor, Determining a residual voltage phasor, characterised in that it comprises the steps of: Determining an active current by projection of the residual current phasor on the residual voltage phasor, Determining of the residual voltage phasor module, Comparing the residual voltage phasor module with a threshold, and in that it comprises the following steps, as long as the residual voltage phasor module remains higher than the threshold or a fraction of the threshold, and for a predetermined number of iterations starting from the moment when the residual voltage phasor module is greater than the threshold: Determining an active current by projection of the residual current phasor on the residual voltage phasor, Determining of the residual voltage phasor module, Comparing the residual voltage phasor module with a threshold, and in that it comprises the following steps, as long as the residual voltage phasor module remains higher than the threshold or a fraction of the threshold, and for a predetermined number of iterations starting from the moment when the residual voltage phasor module is greater than the threshold: Determining (E9, E12) the integral of the active current and of the sign of the integral of the active current, Determining the residual current phasor module, Determining the number of times when the residual current phasor module is greater than a predetermined threshold, during the predetermined number of iterations, If the residual current phasor module is greater than the predetermined threshold at least one time, during the predetermined number of iterations, Determining the location upstream or downstream of the defect according to the number of times when the sign of the integral of the active current was positive or negative during the predetermined number of iterations.