The task of the thesis was to develop a theoretical basis and create a computer program for calculating the distribution of electric and magnetic field strengths and current strength for an infinitely long cylindrical multilayer conductor with an arbitrary number of conductive and dielectric layers. Special attention had to be paid to the dielectric layers. Namely, within the framework of this thesis, a theoretical basis was developed for two models of an infinitely long multilayer cylindrical conductor with an arbitrary number of dielectric layers. In one model, displacement currents were completely neglected, while in the other model displacement currents were neglected only in the conductive layers. In addition to the above, it was necessary to consider the calculation of the internal impedance per unit length of such a conductor. The second chapter of the thesis provides an overview of two models of a multilayer cylindrical conductor with an arbitrary number of dielectric layers. The treatment of dielectric layers as well as the designation of geometric and electrical characteristics of individual layers of a multilayer conductor are described. The third chapter of the thesis provides a theoretical basis for calculating the distribution of electric and magnetic field strengths in one layer of a multilayer conductor. This chapter develops a theory for calculating the field in one layer of a multilayer conductor for both cases of taking displacement currents into account. Both developed models of a multilayer cylindrical conductor with dielectric layers are based on Maxwell’s equations for good conductors, which means that displacement currents in the conductive layers are neglected. However, displacement currents are neglected in one model in the dielectric layers, and are taken into account in the other model. The fourth and fifth chapters of the thesis describe the formation of a system of equations from the boundary and boundary conditions between the layers for both models of a multilayer cylindrical conductor with dielectric layers. The sixth chapter describes the calculation of the internal impedance per unit length for both models of a multilayer conductor. The seventh chapter provides numerical examples where the agreement of the results obtained using the two presented models is analyzed in detail. The analysis includes a comparison of the electric and magnetic field moduli along the cross-section of the conductor as well as the calculation of the internal impedance moduli of the multilayer conductor.