Disclosed are a method and a device for allocating a resource unit on the basis of a container in a wireless LAN. The method for allocating a resource unit in a wireless LAN comprises the steps of: generating, by an AP, a PPDU to be transmitted to a plurality of STAs; and transmitting, by the AP, the PPDU to the plurality of STAs through at least one container allocated on the entire frequency band, wherein the PPDU includes MU/SU transmission indication information and resource allocation information for each container, the MU/SU transmission indication information includes information on whether an SU-based transmission or an MU-based transmission is carried out on the entire bandwidth, and the resource allocation information for each container can include information on the number of STAs allocated to each of the at least one container.