An antenna switching method. When a terminal device is in an idle state, a first target parameter is determined according to signal quality parameters corresponding to downlink signals received by a first quantity of antennas in the terminal device, and some antennas with better signal quality are selected from the first quantity of antennas as first target antennas if the first target parameter is greater than or equal to a first preset threshold, to continue to receive, through the first target antennas, downlink signals from a network device. Therefore, signal quality of the downlink signals received by the first target antennas can be better, thereby improving signal quality of the downlink signals finally received by the terminal device, to improve receiving performance of the terminal device.