The present disclosure relates to methods and devices of accessing a wireless network. The method of accessing a wireless network in a first terminal device includes: detecting a target terminal device waiting access a target wireless network after the first terminal device accesses the target wireless network; generating a plurality of multicast addresses according to access information of the target wireless network; and sending a multicast packet to each of the plurality of multicast addresses, wherein the multicast packet is indicative of the access information and is received by the target terminal device so as to access the target wireless network.