The present disclosure relates to a communication technique and system for converging, with IoT technology, a 5G communication system for supporting a higher data transmission rate beyond a 4G system. The present disclosure may be applied to intelligent services (for example, smart homes, smart buildings, smart cities, smart cars or connected cards, health care, digital education, retail business, security and safety related services, etc.), on the basis of the 5G communication technology and IoT associated technology. According to the present invention, in a method of receiving a MAC PDU, when an unused value is included in a received MAC PDU, the MAC PDU is received through a multicast channel, and the unused value is included in a sub-header of the MAC PDU, the sub-header and a payload portion corresponding to the sub-header are ignored and the remaining sub-header and payload portion are processed.