A method for monitoring a communications channel between a terminal device and a network device is described. The method includes: obtaining a first search space configuration and a second search space configuration. The first search space configuration includes a first search space set and the second search space configuration includes a second search space set, or the first search space configuration includes a first search space parameter and the second search space configuration includes a second search space parameter. The method further includes monitoring a physical downlink control channel (PDCCH) based on the first search space configuration if a first condition is met. The first condition includes: a first timer is not in a running state; or monitoring, by the terminal device, a PDCCH based on the second search space configuration if a second condition is met. The second condition includes a first timer is in a running state.