A method and/or a communications apparatus controls a monitoring of a physical downlink control channel. The method includes: receiving, by a terminal device, a first message sent by a network device, where the first message includes M sleep time sets, and the sleep time is used to indicate a time length in which monitoring the PDCCH is stopped; receiving, by the terminal device, a second message sent by the network device, where the second message includes sleep time indication information, the sleep time indication information is used to indicate a target sleep time index, and the target sleep time index is an index in the M sleep time sets; and stopping, by the terminal device, monitoring the PDCCH in a target time period.