A method and device are provided for determining resource configuration of uplink signal transmission. A method performed by a terminal in a wireless communication system includes receiving, from a base station, a first control message including first configuration information on msg3 repetition, second configuration information on UL or DL configuration, and third configuration information on an SSB; transmitting, to the base station, a random access preamble; receiving, from the base station, an RAR in response to the random access preamble; identifying a first resource for a repetition of a msg3 transmission based on the RAR and the first control message, wherein the first resource does not include a symbol indicated as a downlink by the second configuration information or a symbol indicated by the third configuration information to which the SSB is to be transmitted; and transmitting, to the base station, the msg3 on the identified first resource.