The diffuse reflectance and transmittance of rabbit arteries and veins were studied.476.5 nm wavelength of Ar + laser was used in the experiment.The measurements were performed with two standard integrating sphere systems.The absorption coefficient,scattering coefficient and the changes of total optical intensities I(x),forward scattering flux i(x),backward scattering flux j(x) as a function of thickness of rabbit arteries and veins were evaluated and analyzed from the experimented data by Kubelka Munk model.The results of measurement showed significant difference of diffuse reflectance and transmittance between arteries and veins.Furthermore,the absorption coefficient of arteries were obviously lesser and the scattering coefficient of arteries were obviously bigger than that of veins.The I(x),i(x) and j(x) as a function of thickness of rabbit arteries and veins were also significant difference.