Embodiments of the present invention disclose a clustering method, including: adjusting, by a first device, a beginning of its own first small bandwidth beacon transmission interval to be aligned with a selected empty Beacon SP, setting its own BI to be equal to a synchronization device beacon interval S-BI, and joining, after accordingly adjusting an interval VBI for sending a beacon frame on a large bandwidth channel and an interval SBBI for sending a beacon frame on a small bandwidth channel, a target small bandwidth cluster; or sending a beacon frame including a cluster probe IE over a large bandwidth channel, requesting, by using the cluster probe IE, a synchronization PCP to return cluster synchronization information and control information, and joining the target large bandwidth cluster according the information and a second PCP.