Reconfigurable security system with high flexibility, adaptability and scalability is a hot issue in the field of security research. At present, research on the reconfiguration mechanism is mainly based on the static reconfiguration method. As an active security defense method, it should have the ability of dynamic automatic reconfiguration. In order to solve the problem of modeling and describing dynamic and automatic reconfigurable security system, this paper proposes a new model, SSPE based on intuitionistic logic, and presents its syntax and inference rules. The transformation rules from the specification of security reconfigurable component to SSPE logic expressions are obtained by the method of mapping relationship. In the end, the paper describes the reasoning and generating process of security system reconfiguration based on IPSec protocol. Modeling and expression method based on intuitionistic logic can provide new ideas and methods for the research of reconfigurable security system, which is of great significance.