A method of transmitting repetitions of a physical uplink control channel, PUCCH, in different narrowbands by a terminal in a wireless communication system, the method comprising: receiving a data channel from a base station; and transmitting, to the base station, repetitions of the PUCCH on a first narrowband and a second narrowband of a frequency for transmitting the PUCCH repetitions in response to the reception of the data channel, wherein the transmitting further comprises: identifying consecutive subframes including a first subframe and a second subframe which is consecutive to the first subframe and transmitting a first number of repetitions of the PUCCH transmission on the first narrowband over a first number of subframes including the first subframe which is the last of the first number of subframes and a second number of repetitions of the PUCCH transmission on the second narrowband over a second number of subframes including the second subframe which is the first of the second number of subframes; and performing a frequency retuning between the consecutive subframes from the first narrowband to the second narrowband while transmitting the PUCCH repetitions in the consecutive subframes, by not transmitting the PUCCH repetitions in a last symbol in the first subframe and a first symbol in the second subframe. receiving a data channel from a base station; and transmitting, to the base station, repetitions of the PUCCH on a first narrowband and a second narrowband of a frequency for transmitting the PUCCH repetitions in response to the reception of the data channel, wherein the transmitting further comprises: identifying consecutive subframes including a first subframe and a second subframe which is consecutive to the first subframe and transmitting a first number of repetitions of the PUCCH transmission on the first narrowband over a first number of subframes including the first subframe which is the last of the first number of subframes and a second number of repetitions of the PUCCH transmission on the second narrowband over a second number of subframes including the second subframe which is the first of the second number of subframes; and performing a frequency retuning between the consecutive subframes from the first narrowband to the second narrowband while transmitting the PUCCH repetitions in the consecutive subframes, by not transmitting the PUCCH repetitions in a last symbol in the first subframe and a first symbol in the second subframe. identifying consecutive subframes including a first subframe and a second subframe which is consecutive to the first subframe and transmitting a first number of repetitions of the PUCCH transmission on the first narrowband over a first number of subframes including the first subframe which is the last of the first number of subframes and a second number of repetitions of the PUCCH transmission on the second narrowband over a second number of subframes including the second subframe which is the first of the second number of subframes; and performing a frequency retuning between the consecutive subframes from the first narrowband to the second narrowband while transmitting the PUCCH repetitions in the consecutive subframes, by not transmitting the PUCCH repetitions in a last symbol in the first subframe and a first symbol in the second subframe.