A method for receiving a signal by using resource units each having a plurality of subcarriers in a wireless local area network, WLAN, system, the method comprising: receiving a Physical Protocol Data Unit, PPDU, by using at least one resource unit, RU, allocated for a data field of the receiving station, wherein each RU is one of a first type RU, a second type RU including a larger number of subcarriers than a first type RU and a third type RU including a larger number of subcarriers than a second type RU, wherein the PPDU is received through a predetermined band , the predetermined band including first to fifth frequency bands each being contiguous with one another, a left guard band being contiguous with the first frequency band , and a right guard band being contiguous with the fifth frequency band , wherein, in case a first type or second type RU is allocated to the first frequency band , a leftmost subcarrier of the first frequency band is a null subcarrier, wherein, in case a first type or second type RU is allocated to the second frequency band , a leftmost subcarrier of the second frequency band is a null subcarrier, wherein, in case a third type RU is allocated to the first and second frequency bands , the first and second frequency bands include no null subcarrier, wherein, in case a first type or second type RU is allocated to the fourth frequency band , a rightmost subcarrier of the fourth frequency band is a null subcarrier, wherein, in case a first type or second type RU is allocated to the fifth frequency band , a rightmost subcarrier of the fifth frequency band is a null subcarrier, wherein, in case a third type RU is allocated to the fourth and fifth frequency bands , the fourth and fifth frequency bands include no null subcarrier. receiving a Physical Protocol Data Unit, PPDU, by using at least one resource unit, RU, allocated for a data field of the receiving station, wherein each RU is one of a first type RU, a second type RU including a larger number of subcarriers than a first type RU and a third type RU including a larger number of subcarriers than a second type RU, wherein the PPDU is received through a predetermined band , the predetermined band including first to fifth frequency bands each being contiguous with one another, a left guard band being contiguous with the first frequency band , and a right guard band being contiguous with the fifth frequency band , wherein, in case a first type or second type RU is allocated to the first frequency band , a leftmost subcarrier of the first frequency band is a null subcarrier, wherein, in case a first type or second type RU is allocated to the second frequency band , a leftmost subcarrier of the second frequency band is a null subcarrier, wherein, in case a third type RU is allocated to the first and second frequency bands , the first and second frequency bands include no null subcarrier, wherein, in case a first type or second type RU is allocated to the fourth frequency band , a rightmost subcarrier of the fourth frequency band is a null subcarrier, wherein, in case a first type or second type RU is allocated to the fifth frequency band , a rightmost subcarrier of the fifth frequency band is a null subcarrier, wherein, in case a third type RU is allocated to the fourth and fifth frequency bands , the fourth and fifth frequency bands include no null subcarrier. <EOS>