A method includes: receiving, by a terminal device, indication information on a first serving cell; and performing, by the terminal device, first processing if the indication information indicates not to monitor a PDCCH, where the first processing includes at least one of the following: not monitoring a PDCCH on at least one second serving cell or not monitoring a PDCCH for the at least one second serving cell; or performing, by the terminal device, second processing if the indication information indicates to monitor a PDCCH, where the second processing includes at least one of the following: monitoring a PDCCH on at least one second serving cell or monitoring a PDCCH for the at least one second serving cell.