[en] In this paper, we have discussed the impact of density of the monoclinic material with height on Rayleigh wave’s propagations in anisotropic layer over a monoclinic half space. Two medium layers are being considered in this space, one is an anisotropic medium for the upper layer and a monoclinic media for the lower space, respectively. The governing equations are solved by using the boundary conditions which include the stress and displacement is continuous at the interface, while at the free surface, the stress vanishes. Dispersion equations are obtained for each layer and then solved the governing equations analytically/numerically, and these solutions are displayed graphically, in order to explain the effect of height and density on Rayleigh waves. (author)