A method for determining a phase of a phase conductor belonging to a polyphase electric current distribution network, in particular a three-phase network, wherein the phase of any phase conductor of the network determines an electrical voltage phase shift which exists between said conductor and a reference phase conductor of the network, the network including modems which are each connected to one of the phase conductors of said network, and which are adapted to communicate according to a power line carrier, or PLC, protocol, one of the modems being connected to the reference phase conductor, the method characterised in that it comprises the sequence of the following steps, executed for one of the phase conductors of the network, called target conductor, which is identified and whose phase is to be determined: /1/ constructing several sequences of phase conductors of the network, different from each other and each starting with the reference phase conductor, each ending with the target conductor, and each containing an ordered selection of one or more network phase conductors, which are intermediate between the reference phase conductor and the target conductor in each sequence, and for which an electrical voltage phase shift which exists between two conductors which are successive in one of the sequences has been obtained by a modem which is connected to one of said two conductors, for all pairs of successive conductors of each sequence; /2/ for each sequence constructed in step /1/, calculating an addition result as a sum of the phase shifts of all pairs of successive conductors of said sequence; /3/ considering that the addition results calculated in step /2/ form a statistical distribution, and taking into account a congruence between different values which represent one same phase shift, determining which of said addition results has a highest frequency of occurrence; and /4/ declaring the addition result which has the highest frequency of occurrence as the phase of the target conductor if said highest frequency of occurrence is greater than or equal to a predefined reliability threshold, otherwise declaring the phase of the target conductor as being indeterminate if said highest frequency of occurrence is less than the reliability threshold. the network including modems which are each connected to one of the phase conductors of said network, and which are adapted to communicate according to a power line carrier, or PLC, protocol, one of the modems being connected to the reference phase conductor, the method characterised in that it comprises the sequence of the following steps, executed for one of the phase conductors of the network, called target conductor, which is identified and whose phase is to be determined: /1/ constructing several sequences of phase conductors of the network, different from each other and each starting with the reference phase conductor, each ending with the target conductor, and each containing an ordered selection of one or more network phase conductors, which are intermediate between the reference phase conductor and the target conductor in each sequence, and for which an electrical voltage phase shift which exists between two conductors which are successive in one of the sequences has been obtained by a modem which is connected to one of said two conductors, for all pairs of successive conductors of each sequence; /2/ for each sequence constructed in step /1/, calculating an addition result as a sum of the phase shifts of all pairs of successive conductors of said sequence; /3/ considering that the addition results calculated in step /2/ form a statistical distribution, and taking into account a congruence between different values which represent one same phase shift, determining which of said addition results has a highest frequency of occurrence; and /4/ declaring the addition result which has the highest frequency of occurrence as the phase of the target conductor if said highest frequency of occurrence is greater than or equal to a predefined reliability threshold, otherwise declaring the phase of the target conductor as being indeterminate if said highest frequency of occurrence is less than the reliability threshold. /1/ constructing several sequences of phase conductors of the network, different from each other and each starting with the reference phase conductor, each ending with the target conductor, and each containing an ordered selection of one or more network phase conductors, which are intermediate between the reference phase conductor and the target conductor in each sequence, and for which an electrical voltage phase shift which exists between two conductors which are successive in one of the sequences has been obtained by a modem which is connected to one of said two conductors, for all pairs of successive conductors of each sequence; /2/ for each sequence constructed in step /1/, calculating an addition result as a sum of the phase shifts of all pairs of successive conductors of said sequence; /3/ considering that the addition results calculated in step /2/ form a statistical distribution, and taking into account a congruence between different values which represent one same phase shift, determining which of said addition results has a highest frequency of occurrence; and /4/ declaring the addition result which has the highest frequency of occurrence as the phase of the target conductor if said highest frequency of occurrence is greater than or equal to a predefined reliability threshold, otherwise declaring the phase of the target conductor as being indeterminate if said highest frequency of occurrence is less than the reliability threshold.