The present disclosure relates to a communication technique for combining a 5G communication system for supporting a higher data transmission rate than a 4G system with an IoT technology, and a system therefor. The present disclosure can be applied to 5G communication and IoT related technology-based intelligent services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail business, security and safety related services, etc.). Disclosed is a technology for adding uplink data to a radio resource control (RRC) connection request message corresponding to an RA response message and transmitting the same to a base station when the terminal is in an RRC deactivated state in a method for transmitting, by a terminal, uplink data in a wireless communication system.