The factor group symmetry analysis method was used to analyse the Raman spectra of neodymium-doped yttrium orthoanadate Nd:YVO4 which were measured at room temperature with different geometrical configurations. All the Raman peaks were assigned on the basis of the group theory and lattice dynamics thoery. According to the peak numbers of the Raman spectra, we concluded that the primitive cell of Nd:YVO4 contains four formula units.