A method for transmitting reference signal, a method for receiving reference signal, base station and user equipment are provided. The method includes: obtaining a plurality of possible transmission positions of the reference signal according to a position where a setting signal is located, wherein the setting signal is located in the reference signal and is used to determine an index of the reference signal, and the plurality of possible transmission positions comprise an initial possible transmission position of the reference signal; performing channel detection before transmitting the reference signal at each of the possible transmission positions; and transmitting, in response to detecting that a channel is idle, the reference signal at a corresponding possible transmission position; wherein the reference signal includes a SSB, and the setting signal comprises PBCH in the SSB; the indexes of the reference signal corresponding to the plurality of possible transmission positions are the same.