The constant increase in the number of threats to the security of critical infrastructure objects, which include socio-cyberphysical systems, leads to a decrease in the quality of security services and the level of security of infrastructure elements. The object of research is the process of building a complex system of protection in socio-cyberphysical systems. The imperfection of the mechanisms for ensuring the security of critical infrastructure objects, which include socio-cyberphysical systems, the technological complexity of identifying new security threats necessitates an urgent need for a radical revision of the current approaches to its provision. So, it becomes clear that the development of a new approach to ensuring the security of information resources in socio-cyberphysical systems is needed. The article proposes a new approach to the methodological foundations of building multi-contour information protection systems with internal and external circuits on each of the platforms of socio-cyberphysical systems. This approach is based on a universal classifier of threats, which takes into account not the technical aspect of threats, but also their integration with social engineering methods, their synergy of hybridity. The sociopolitical influence on the realization of threats is taken into account, and practical mechanisms for providing basic security services based on post-quantum algorithms are also proposed. To provide basic security services in the proposed multi-contour protection system, it is proposed to use post-quantum algorithms – McEliece crypto-code constructions, which provide Perr=10-9–10-12, safe time Tsec=1025–1035 group operations. Within the framework of the proposed approach, the problem of increasing the level of information security has been formalized and further ways of solving it have been determined