This application discloses an uplink access method, a base station, and user equipment. The method of this application includes: in a process in which user equipment performs initial random access to a high-frequency base station, allocating, by the high-frequency base station, a non-contention-based sequence to the user equipment, and sending the non-contention-based sequence to the user equipment by using a first random access response message; after the user equipment completes the initial random access to the high-frequency base station and in a periodical beam training process, determining, by the high-frequency base station, an optimal receiving wide beam of the high-frequency base station and an optimal sending narrow beam of the user equipment by detecting, on each receiving wide beam of the high-frequency base station, the non-contention-based sequence sent by the user equipment; and sending, by the high-frequency base station, a second random access response message to the user equipment.