Example methods and apparatus for configuring a transmit port of a downlink reference signal are described. One example method includes indicating configurations corresponding to a plurality of transmit ports to a terminal device by a network device by using first indication information. Each transmit port may be associated with one piece of delay information, transmit ports associated with same delay information correspond to a same configuration, and at least two transmit ports associated with different delay information correspond to different configurations. The terminal device may receive, based on a configuration corresponding to each transmit port, downlink reference signals sent by the plurality of transmit ports.