The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The present disclosure relates to a method and apparatus for transmitting uplink (UL) data in a wireless communication system. A method includes receiving configuration information for a grant-free UL transmission, the configuration information including information on a number of repetitive transmissions and period information; identifying a plurality of resources for the repetitive transmissions in a period based on the configuration information; identifying a resource for an initial transmission of the UL data based on a value of a redundancy version (RV) associated with the resource; and performing the initial transmission of the UL data on the identified resource. A number of former resources F are capable of being used for the initial transmission of the UL data among the plurality of resources for the repetitive transmissions. The number of the former resources F is determined based on the number of the repetitive transmissions.