Beacon transmission method and device, and network access method and device

Provided are a beacon transmission method, a network access method, a coordinator, and a device, which allow for a device located in an interference zone to correctly detect a beacon and join a network normally. The method is: the coordinator using a first beacon time slot of a current super-frame to send a beacon, and upon sending said beacon, receiving a first beacon request frame sent by the device; the first beacon request frame being used for indicating that the device is in an interference zone between the first network in which the coordinator is located and a zone of at least one second network; the coordinator, after receiving the first beacon request frame, uses the first beacon time slot and second beacon time slot of each super-frame of the N super-frames starting the subsequent super-frame, wherein N≥1 and N is a positive integer. Thus the probability of the device correctly detecting a beacon is increased, such that the device is able to join a network normally and promptly perform interference coordination.