A Station (STA) in a wireless communication system, the STA including a transceiver configured to transmit and receive a wireless signal; and a processor configured to control the transceiver. Further, the processor is further configured to: receive, from An access point (AP), a downlink (DL) multi-user (MU) Physical Protocol Data Unit (PPDU), wherein the DL MU PPDU includes a DL data and trigger frame for an uplink (UL) orthogonal frequency-division multiple access (OFDMA) transmission; and transmit, to the AP, an UL MU PPDU generated based on the DL MU PPDU, wherein the trigger frame is transmitted in a first frequency region of the DL MU PPDU, and the DL data is transmitted in a second frequency region of the DL MU PPDU, when the trigger frame is for multiple stations (STAs), and wherein the first frequency region and the second frequency region are different frequency region.