This application discloses example device-to-device (D2D) transmission methods and communication apparatuses. One example method includes receiving, by a station, a trigger frame sent by an access point, where the trigger frame includes a user information field, the user information field includes an identifier of the station, resource allocation information, first indication information, and second indication information, the first indication information indicates that a resource unit indicated by the resource allocation information is used for D2D transmission, and the second indication information indicates that the station is a sender or a receiver of the D2D transmission. The D2D transmission is performed by the station on the resource unit indicated by the resource allocation information.