This application provides a method for reducing interference between a radar and an uplink frequency band. A first network device obtains a characteristic of a radar signal on the uplink frequency band, and determines a corresponding protection measure based on the characteristic of the radar signal, to reduce interference between the radar signal and the uplink frequency band. In this way, when 5G communication collides with the radar in time domain and frequency domain of the uplink frequency band, the 5G communication and the radar can still coexist. This improves utilization of a wireless spectrum.