A reference signal transmission method, wherein the method comprises: determining, by a transmit-end device, a target time-frequency resource occupied by a a plurality of reference signals in a plurality of transmission units comprising a plurality of symbols and subcarriers, wherein each of the plurality of reference signals corresponds to at least one antenna port, wherein each of the plurality of transmission units comprises a first part, in each transmission unit, the target time-frequency resource is located on at least one symbol of the plurality of symbols in the first part, and different reference signals are located in different transmission units; and sending, by the transmit-end device, the plurality of reference signals to a receive-end device by using the target time-frequency resource in the plurality of transmission units; wherein the plurality of transmission units comprises at least two contiguous transmission units and the plurality of reference signals are centrally mapped to the at least two contiguous transmission units; wherein the method further comprises: determining, by the transmit-end device, configuration indication information, wherein the configuration indication information comprises a quantity of transmission units occupied by the plurality of reference signals, a quantity of symbols in the first part, and location information of a symbol on which each of the plurality of reference signals is located, wherein the location information comprises at least one of a symbol identifier and a location offset value, and the location offset value of the symbol on which each of the pluarliy of reference signals is located is a location offset value between the symbol on which the reference signal is located and a last symbol of a transmission unit in which the reference signal is located; and sending, by the transmit-end device, the configuration indication information to the receive-end device. determining, by a transmit-end device, a target time-frequency resource occupied by a a plurality of reference signals in a plurality of transmission units comprising a plurality of symbols and subcarriers, wherein each of the plurality of reference signals corresponds to at least one antenna port, wherein each of the plurality of transmission units comprises a first part, in each transmission unit, the target time-frequency resource is located on at least one symbol of the plurality of symbols in the first part, and different reference signals are located in different transmission units; and sending, by the transmit-end device, the plurality of reference signals to a receive-end device by using the target time-frequency resource in the plurality of transmission units; wherein the plurality of transmission units comprises at least two contiguous transmission units and the plurality of reference signals are centrally mapped to the at least two contiguous transmission units; wherein the method further comprises: determining, by the transmit-end device, configuration indication information, wherein the configuration indication information comprises a quantity of transmission units occupied by the plurality of reference signals, a quantity of symbols in the first part, and location information of a symbol on which each of the plurality of reference signals is located, wherein the location information comprises at least one of a symbol identifier and a location offset value, and the location offset value of the symbol on which each of the pluarliy of reference signals is located is a location offset value between the symbol on which the reference signal is located and a last symbol of a transmission unit in which the reference signal is located; and sending, by the transmit-end device, the configuration indication information to the receive-end device. determining, by the transmit-end device, configuration indication information, wherein the configuration indication information comprises a quantity of transmission units occupied by the plurality of reference signals, a quantity of symbols in the first part, and location information of a symbol on which each of the plurality of reference signals is located, wherein the location information comprises at least one of a symbol identifier and a location offset value, and the location offset value of the symbol on which each of the pluarliy of reference signals is located is a location offset value between the symbol on which the reference signal is located and a last symbol of a transmission unit in which the reference signal is located; and sending, by the transmit-end device, the configuration indication information to the receive-end device.