A reference signal transmission method, wherein the method comprises: determining (101, 901), by a first user equipment, at least one base sequence corresponding to at least one frequency-domain resource group that is on a symbol carrying the reference signal and that is used to send the reference signal, wherein one frequency-domain resource group of the at least one frequency-domain resource group is corresponding to one base sequence, wherein different base sequences are determined based on different frequency-domain resource groups, and the reference signal is generated based on the base sequences, and is mapped to a corresponding time-frequency resource; and generating (102, 902), by the first user equipment, the reference signal based on the at least one base sequence, and mapping the reference signal to the time-frequency resource whose time domain is the symbol and whose frequency domain is the at least one frequency-domain resource group; wherein the determining, by the first user equipment, the at least one base sequence corresponding to at least one frequency-domain resource group that is on the symbol carrying the reference signal and that is used to send the reference signal comprises: determining, by the first user equipment, a first base sequence corresponding to a first frequency-domain resource group, and determining a second base sequence corresponding to a second frequency-domain resource group; and the generating, by the first user equipment, the reference signal based on the at least one base sequence, and mapping the reference signal to the time-frequency resource whose time domain is the symbol carrying the reference signal and whose frequency domain is the at least one frequency-domain resource group comprises: generating, by the first user equipment, a first reference signal sequence of the reference signal based on the first base sequence, and mapping the first reference signal sequence to a time-frequency resource whose time domain is the symbol and whose frequency domain is the first frequency-domain resource group; and generating, by the first user equipment, a second reference signal sequence of the reference signal based on the second base sequence, and mapping the second reference signal sequence to a time-frequency resource whose time domain is the symbol and whose frequency domain is the second frequency-domain resource group; and wherein the first frequency-domain resource group and the second frequency-domain resource group correspond to two different frequency-domain combs on the time-frequency-domain resource whose time domain is the symbol, the first frequency-domain resource group and the second frequency-domain resource group comprise a same quantity of subcarriers. determining (101, 901), by a first user equipment, at least one base sequence corresponding to at least one frequency-domain resource group that is on a symbol carrying the reference signal and that is used to send the reference signal, wherein one frequency-domain resource group of the at least one frequency-domain resource group is corresponding to one base sequence, wherein different base sequences are determined based on different frequency-domain resource groups, and the reference signal is generated based on the base sequences, and is mapped to a corresponding time-frequency resource; and generating (102, 902), by the first user equipment, the reference signal based on the at least one base sequence, and mapping the reference signal to the time-frequency resource whose time domain is the symbol and whose frequency domain is the at least one frequency-domain resource group; wherein the determining, by the first user equipment, the at least one base sequence corresponding to at least one frequency-domain resource group that is on the symbol carrying the reference signal and that is used to send the reference signal comprises: determining, by the first user equipment, a first base sequence corresponding to a first frequency-domain resource group, and determining a second base sequence corresponding to a second frequency-domain resource group; and the generating, by the first user equipment, the reference signal based on the at least one base sequence, and mapping the reference signal to the time-frequency resource whose time domain is the symbol carrying the reference signal and whose frequency domain is the at least one frequency-domain resource group comprises: generating, by the first user equipment, a first reference signal sequence of the reference signal based on the first base sequence, and mapping the first reference signal sequence to a time-frequency resource whose time domain is the symbol and whose frequency domain is the first frequency-domain resource group; and generating, by the first user equipment, a second reference signal sequence of the reference signal based on the second base sequence, and mapping the second reference signal sequence to a time-frequency resource whose time domain is the symbol and whose frequency domain is the second frequency-domain resource group; and wherein the first frequency-domain resource group and the second frequency-domain resource group correspond to two different frequency-domain combs on the time-frequency-domain resource whose time domain is the symbol, the first frequency-domain resource group and the second frequency-domain resource group comprise a same quantity of subcarriers.