While developing a new modern device for diagnostics and monitoring of the grounding system in real time, the existing modern devices for diagnostics and monitoring of the railway traction network have been analyzed and specific features of high-speed rail traffic development have been studied. The paper presents the existing devices and methods for diagnostics and monitoring of the power supply elements of railway traction. The basic principles of operation of the devices used are given and their advantages and disadvantages are analyzed. The presented analysis makes it possible to estimate the new tendencies in diagnostics and monitoring system development and to summarize further prospects of their implementation and improvement.