A method and an apparatus for mapping a reference signal are disclosed. The method includes: mapping a target-class signal to a target symbol, where the target symbol is some symbols in a first symbol set on a time-frequency resource block, the first symbol set is a set of some symbols or all symbols on the time-frequency resource block, the target-class signal has at least two functions, and the at least two functions include a function of estimating a parameter that affects signal transmission; and mapping the reference signal to a symbol in the first symbol set other than the target symbol, where the reference signal has the function of estimating a parameter that affects signal transmission. Embodiments of the present invention can save resources.