Annotation: In this article, was conducted an analysis of approaches of building an information security system in the leading countries of the world. The analysis of the approaches of building an information security system in the leading countries of the world found that the information security system relates to complex. However, there is currently no single approach of the synthesis of its structure. The author of this article propose to implement the synthesis of information security system by forming the properties of the system, requirements for it and the performed functions the structural synthesis of its system - the formation of elements of the system and then perform a parametric synthesis of the system with the definition of parameters of the structure elements. Formation of system properties, requirements to it and performed functions is carried out on the basis of analysis features of the applicability of the developed system and tasks performed with its using. Also, an analysis of traditional approaches to the implementation of structural synthesis of the glass-bottom system, namely, the heuristic synthesis of the structure and methods of one-and-many and multi-criteria optimization. Alternative variants of system construction can be formed as heuristic methods, and with using of mathematical synthesis methods. In turn, the procedure of choosing the optimal structure of the system from the set of alternatives can be realized by using the optimization methods as onefactorial, and multicriterion model. Thus, during the synthesis of the information security system of the state power bodies of Ukraine, an approach was developed for the formation of multicriterial mathematical models of structural and parametric synthesis of information systems with the accumulation of targeted information.