This application discloses a method and an apparatus for transmitting a pilot signal, so that more flexible resource configuration can be achieved, thereby improving resource usage. The method includes: determining, by a transmit end device based on prestored N pilot patterns, a target time-frequency resource for transmitting a pilot signal, where the target time-frequency resource corresponds to a total quantity of layers of a to-be-transmitted data stream, the N pilot patterns are different from each other, and N is a natural number greater than or equal to 1; and sending, by the transmit end device, indication information to a receive end device, where the indication information is used to instruct the receive end device to transmit the pilot signal to the transmit end device based on the target time-frequency resource.