Raman spectra of a batch of potassium lithium niobate(KLN) crystals with different compositions were investigated.The analysis results show the striking effects of Li content on these Raman peaks.For the KLN sample with small Li content,the three character peaks belong to ~(7-) O_h octahedron show simple peak,and the weak peaks in the wavelength range of 100~400 cm~(-1) are regarded to relate to the Li ions in C lattice.With the raise of Li content in crystal,the peaks belong to ν_2 mode are partly split, and the peak belongs to ν_5 mode is broadened in the spectrum corresponding to scattering geometry X(ZY)Z.When the Li content approaches to chemical composition,the peaks belong to ν_5 mode are split,the peaks belong to ν_1 mode and ν_2 mode are partly split too.