The present invention provides a method and device for generating and mapping a Channel State Information Reference Signal (CSI-RS) sequence, and the method includes: generating a pseudo-random sequence according to a pseudo-random sequence initial value, performing a Quadrature Phase-Shift Keying (QPSK) modulation on the pseudo-random sequence, and obtaining a first CSI-RS sequence according to maximum bandwidth of system; and cutting the first CSI-RS sequence according to the actual bandwidth of the system, obtaining a second CSI-RS sequence, and mapping the second CSI-RS sequence to a time frequency location of a CSI-RS antenna port. The CSI-RS reference signal sequence can be generated or obtained respectively at the UE terminal and eNB terminal in accordance with the stated methods for generating and mapping the reference sequence according to known parameters by the present invention, so that the calculated CSI-RS sequence can be utilized to measure the channel at the UE terminal.