The present disclosure relates to: a communication technique for merging IoT technology with a 5G communication system for supporting a data transmission rate higher than that of a 4G system; and a system therefor. The present disclosure can be applied to an intelligent service (for example, smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail businesses, and security- and safety-related services) on the basis of a 5G communication technology and an IoT-related technology. The present disclosure provides a method and a device for setting, indicating and operating a HARQ process ID.