Disclosed are an uplink transmission method in a wireless communication system and an apparatus therefor. In detail, the method for a uplink (UL) multi-user (MU) transmission by a station (STA) in a wireless communication system includes receiving a trigger frame including frequency resource allocation information in a subband unit for orthogonal frequency division multiple access (OFDMA) transmission from an access point (AP), and transmitting a UL MU PPDU based on the frequency resource allocation information, wherein the UL MU PPDU includes a high efficiency-short training field (HE-STF), a high-efficiency-long training field (HE-LTF), and a data field, and the HE-STF, the HE-LTF, and the data field are transmitted in a subband indicated by the frequency resource allocation information.