Aim. The aim of the paper is to develop a method that would allow for integrated experimental, computational, analytical and expert assessment of the vulnerabilities of satellite communication networks, feasibility of information technology interference by intruders against such vulnerabilities and probability of fault tolerance under the chosen information protection solutions, trusted information technologies and fault tolerance sensors. The paper shows the relevance and importance of the method of increasing fault tolerance of satellite communication networks under information technology interference in service control channels and satellite equipment data. The authors examine targeted information technology interference that causes malfunction of satellite modems, control stations and connected user computer networks. The paper shows the unique nature of satellite communication networks operation due to the global operating range, availability of broadband radio signals from communication and retransmission spacecraft for technical analysis and processing within the operating range, potential possibility of unauthorized connection to communication services. The primary direction of development of procedural and process engineering guidelines on protection and fault tolerance of satellite communication networks are defined. Methods. A method has been developed that is based on three components: model of experimental identification of satellite communication network vulnerabilities; simulation, computational and analytical model of detection and identification of threats of information technology interference; decision-making algorithm for improvement of the fault tolerance of a satellite communication network under information technology interference. The model of experimental detection of satellite communication network vulnerability allows, as part of bench tests, establishing connections between existing vulnerabilities of the hardware and software of satellite modems, control stations, user networks and the potential information technology interferences by intruders. As part of the vulnerability model the authors describe the certificates of vulnerable radio technical and information technology parameters of the satellite communication network signals, as well as suggest an analytic expression for calculating the probability of detection of such network vulnerabilities. The paper presents a computational and analytical model of detection and identification of information technology interference threats as a structure of advanced means of detection, prevention and elimination of the consequences of information technology interference in satellite communication networks and the mathematical expression for identification of conditional probability of materialization of the threat of information technology interference in satellite communication networks. An algorithm is considered for improvement of fault tolerance of satellite communication networks under information technology interference, including preparation of parameters and evaluation of the fault tolerance of a satellite communication network, adjustment of the parameters of satellite communication network, information security facilities and fault tolerance sensors, situational adjustment of satellite communication network fault tolerance solutions. Conclusions. It is noted that the developed method enables improved fault tolerance of satellite communication networks under information technology interference based on a set of interconnected procedures of the model of experimental detection of satellite communication network vulnerabilities on testbed; simulation, computational and analytical models of detection and identification of information technology interference threats; application of the decision-making algorithm of improvement of satellite communication network fault tolerance.