A method and a device for receiving a PPDU in a wireless LAN system are presented. Particularly, a receiving STA receives a PPDU from a transmitting STA through a broadband and decodes the PPDU. The PPDU includes a first signal filed and a data field. A 160 MHz band includes first and second 80 MHz segments if the broadband is the 160 MHz band. The first 80 MHz segment includes first to fourth 20 MHz channels, and the second 80 MHz segment includes fifth to eighth 20 MHz channels. The first signal field includes first and second signal CCs for the first 80 MHz segment and includes third and fourth signal CCs for the second 80 MHz segment.