A communications device in a high-frequency system, including: a scan module, configured to use a single beam for each space S region in a to-be-scanned sector of a cell to poll or cover all time T regions in the S region in a time-division manner, and send a synchronization sequence to user equipment in the T region by using a preset frame structure; and a determining module, configured to receive a sequence that is fed back by the user equipment, determine a location of the user equipment according to the sequence, and determine, according to the location of the user equipment, a serving beam for a base station to communicate with the user equipment, to confirm that scanning for the user equipment is completed. The embodiments of the present invention further provide a scanning method in a high-frequency system.