Various embodiments provide a method for receiving reference signal and a method for sending a reference signal. In those embodiments, a terminal device can determine a location of a resource element to which a reference signal is mapped. The terminal device can determine a reference signal sequence corresponding to the resource element. The index of each element in the reference signal sequence is determined based on a resource block index of a resource block corresponding to the resource element, a quantity of resource elements that carry the reference signal in the resource block, a resource block offset, or an inter-symbol offset. The terminal device can receive the reference signal by using the resource element, and performing channel estimation or channel sounding based on the received reference signal and the reference signal sequence. Therefore, the terminal device can complete channel estimation without learning of a system bandwidth.