An automatic impedance matching method of a radio-frequency chain comprising: an impedance matching network having an input and an output, a first radio-frequency device connected to said input and a second radio-frequency device connected to said output, said impedance matching network having a reconfigurable topology and comprising a plurality of reactive elements (C A, L A, C B, L B, C C, L C), at least one of which exhibits a variable reactance and having losses resulting from their interfering resistive components, the method comprising the following steps of: a) measuring at least a current and a voltage at the input or at the output of said impedance matching network; b) computing a complex impedance Z m, defined by the ratio between the voltage and the current that are measured by taking account of their phase shift and representing an input impedance of said impedance matching network or an output impedance of said impedance matching network, depending on whether the measurements in step a) have been taken at the input or at the output of said impedance matching network; c) from said complex impedance Z m, from the topology and from the known present values of the reactive elements of said impedance matching network, computing the value of a complex impedance Z d that is representative of an output impedance of said first radio-frequency device or of an input impedance of said second radio-frequency device, depending on whether the measurements in step a) have been taken at the input or at the output of said impedance matching network; d) for a plurality of possible topologies of said impedance matching network, computing new reactance values for said or for each said reactive element having a variable reactance, so that the load impedance Z DME of said first radio-frequency device or the input impedance Z DSM of said second radio-frequency device takes a value as close as possible to a predefined nominal value Z opt; e) choosing, among said topologies of said impedance matching network, the one that minimizes losses when the reactance of said or of each said reactive element having a variable reactance takes the value computed in step d); and f) configuring the impedance matching network so that it takes the topology determined in step e) and so that the reactance of said or of each said reactive element having a variable reactance takes the value computed in step d). a) measuring at least a current and a voltage at the input or at the output of said impedance matching network; b) computing a complex impedance Z m, defined by the ratio between the voltage and the current that are measured by taking account of their phase shift and representing an input impedance of said impedance matching network or an output impedance of said impedance matching network, depending on whether the measurements in step a) have been taken at the input or at the output of said impedance matching network; c) from said complex impedance Z m, from the topology and from the known present values of the reactive elements of said impedance matching network, computing the value of a complex impedance Z d that is representative of an output impedance of said first radio-frequency device or of an input impedance of said second radio-frequency device, depending on whether the measurements in step a) have been taken at the input or at the output of said impedance matching network; d) for a plurality of possible topologies of said impedance matching network, computing new reactance values for said or for each said reactive element having a variable reactance, so that the load impedance Z DME of said first radio-frequency device or the input impedance Z DSM of said second radio-frequency device takes a value as close as possible to a predefined nominal value Z opt; e) choosing, among said topologies of said impedance matching network, the one that minimizes losses when the reactance of said or of each said reactive element having a variable reactance takes the value computed in step d); and f) configuring the impedance matching network so that it takes the topology determined in step e) and so that the reactance of said or of each said reactive element having a variable reactance takes the value computed in step d).