This application discloses a reference signal sending method, a base station, and user equipment, to relieve a problem of low utilization of time-frequency resources. The method may include receiving, by a base station, a measurement result, sent by user equipment (UE), of a downlink reference signal from a serving cell of the UE, where the base station is a base station to which the serving cell belongs. The method may also include determining, by the base station based on the measurement result, whether a predetermined handover preparation condition is met. When the predetermined handover preparation condition is met, the method may include instructing, by the base station, a neighboring cell to send the downlink reference signal to the UE using a time-frequency resource configured by the base station, where the neighboring cell does not send the downlink reference signal to the UE before the neighboring cell is instructed. Furthermore, the method may include instructing, by the base station, the UE to receive the downlink reference signal using the time-frequency resource configured by the base station.