Embodiments of the present disclosure disclose a method and an apparatus for transmitting an uplink signal, which can efficiently utilize uplink frequency-selectiveness, thereby improving uplink spectral efficiency. The method includes: determining, by a first terminal device, an uplink multiple access scheme for an uplink control signal according to whether a time domain resource unit used for transmitting the uplink control signal is also used for transmitting uplink data; and transmitting, by the first terminal device, the uplink control signal by using the determined uplink multiple access scheme.