The article shows the possibility of applying the methodology of synthesizing the parameters of the maintenance strategy of the mobile communication system. On the basis of Markov model the estimation of functional safety index of mobile communication system, namely frequency of getting into an accident situation from the value of the period of planned preventive maintenance, duration of repair works, etc. is carried out. Feature of the proposed approach is that the designer has the opportunity to choose appropriate parameters of maintenance strategy still at the stage of system-technical design, when the mobile communication system exists as a concept.