A method for transmitting uplink demodulation reference signal (DMRS) includes: receiving, by a terminal device, first DMRS configuration information sent by a network device, the first DMRS configuration information indicating a type of a DMRS sequence; receiving, by the terminal device, second DMRS configuration information sent by the network device, the second DMRS configuration information indicating at least one configuration parameter of: an antenna port configuration of DMRS, a physical resource configuration of DMRS, or a sequence configuration of DMRS; determining, by the terminal device, a configuration parameter indicated by the second DMRS configuration information according to the first DMRS configuration information; determining, by the terminal device, a transmission parameter of DMRS according to the configuration parameter indicated by the second DMRS configuration information; and transmitting, by the terminal device, DMRS to the network device according to the transmission parameter.