Embodiments of the present disclosure provide a beam identifier obtaining method and apparatus, a device, and a system. The method includes: determining, by a base station, a signal corresponding to a beam identifier; sending, by the base station, the signal by using a beam corresponding to the beam identifier, so that user equipment detecting the signal obtains the beam identifier according to the signal; and when receiving the beam identifier fed back by the user equipment, communicating, by the base station, with the user equipment by using the beam corresponding to the beam identifier.