The article examines the conception of multilevel train safety control, according to which the safety is provided by hierarchic system, based on complex locomotive safety system, with extensions, that include the using of data of global positioning systems GLONASS/GPS, as well as digital maps of station-to-station blocks and station layouts, that are formed on the basis of united coordinates data base. The article also describes the formation and technical implementation of levels for provision of safety. The article provides the classification of rolling stock control and diagnostics systems. It also analyses the features of building and operating, advantages and disadvantages of control systems: stationary and inaction; external and built-in; manual, automated and computer-aided. It was shown, that multilevel safety system includes as technical systems of automated and computer-aided control and diagnostics of rolling stock of train in-action (ASKPS), and the algorithms of its operation. The conclusion was made, that ASKPS is a complex multi-dimensional dynamic system, that works under significant number of destabilizing factors. The paper shows the interactions of rolling stock, as an object of control, with ASKPS within multilevel safety system, as well as the possibilities of routine control and forecast of condition of railway rolling stock object by existing systems. Because of the final hardware and information reliability of its components, the ASKPS system itself is liable to failures. For real-time assessment of ASKPS condition its own built-in control system is used. There is also generalised structure of ASKPS with detailed analysis of interacting devices and with the lists of problems, that are solved by each device under the influence of adverse factors as on the object itself, and on the control system. The conclusion was drawn, that because of the complexity of the structure and the variety of algorithms for operation of ASK PS it should be carried out by highly skilled professionals, that requires its special training.