A method and apparatus for performing a random access procedure in a narrowband internet-of-things (NB-IoT) carrier in a wireless communication system is provided. A user equipment (UE) transmits a random access preamble to a network, receives a random access response from the network, determines resources of scheduled uplink (UL) transmission, and performs the scheduled UL transmission to the network. A number of repetitions and a number of tones for the scheduled UL transmission are determined by the random access preamble.