Provided are a communication method and system that combine the 5G communication system with IoT technology to support a data rate higher than that of the 4G system. The present disclosure is based on 5G communication technology and IoT related technology and can be applied to intelligent services (e.g., smart home, smart building, smart city, smart or connected car, health care, digital education, retail business, security, and safety related services). A method is provided that enables the terminal and the 5G network to check each other's capability information to achieve interworking between network slices defined differently by different mobile network operators. The method includes receiving system information associated with a network slice; transmitting, to an access and mobility management function (AMF) entity of a visited public land mobile network (VPLMN), a first message, in case that the system information is associated with a base station corresponding to the VPLMN; and receiving, from the AMF entity, a second message including allowed network slice selection assistance information (NSSAI) for the terminal.