Embodiments of the present invention disclose a radio frame transmission method and a wireless network device. The method includes: receiving PRACH trigger information that is carried in a first transmission subframe in a first radio frame and that is sent by a first wireless network device; and sending, to the first wireless network device in response to the PRACH trigger information, a preamble sequence carried in a second transmission subframe in a second radio frame, where there is a preset first mapping relationship between a subframe number of the first transmission subframe and a subframe number of the second transmission subframe, and a structure of a transmission subframe in the first radio frame is different from a structure of a transmission subframe in the second radio frame.