A cell measurement method and cell measurement apparatus, the method including receiving, by a terminal device, first information from a network device, where the first information indicates a measurement parameter used by the terminal device to perform cell measurement in an idle state or an inactive state, and a detection signal for the cell measurement includes at least a synchronization sequence or physical broadcast channel block (SSB) or a channel state information reference signal (CSI-RS), and sending, by the terminal device, a measurement result of the cell measurement to the network device based on the first information.