The purpose of this master's thesis is to explain the principle of distribution network reconfiguration using a computer program and to investigate the impact of reconfiguring the active distribution network on voltage conditions and losses. In electrical distribution networks, high power losses and inefficient voltage regulation pose a significant challenge. There are various methods to address these issues, including reactive power compensation, increasing impedance, load balancing, and increasing conductor cross-sections. However, implementing these methods often requires substantial financial investments. Alternatively, network reconfiguration stands out as an efficient approach to reducing energy losses and improving voltage profiles without significant capital expenditures. In the third chapter of the thesis, different techniques for minimizing losses in the distribution network are described, highlighting their advantages and disadvantages, and a comparison of these techniques is conducted. The fourth chapter provides a detailed description of the medium-voltage distribution network model used for reconfiguration. The model was developed using the EasyPower software, and this chapter explains the parameters of the network model. The fifth chapter includes an analysis of the reconfiguration of a test network, also conducted using EasyPower. It presents the results of voltage profiles and losses for three different cases labeled A, B, and C. Finally, this chapter concludes with a parallel comparison of the best results obtained in these cases. This thesis presents a theoretical framework and practical application of network reconfiguration to reduce energy losses and enhance the electrical power systems, with a particular emphasis on the cost-effectiveness of this approach.