Thediffusereflectanceandtransmittanceofhumanveinswerestudied.AnHe Nelaser (632.8 nm) was used in the experiment.The measurements were performed with two standard integrating sphere system.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 human veins were evaluated and analyzed from the experimented data by Kubelka Munk (K M) model.The results of measurement showed that significant difference of diffuse reflectance and transmittance between different veins at 632.8 nm wavelength of He Ne laser.Furthermore,the absorption coefficient and the scattering coefficient of different veins were obviously different.The changes of I(x),i(x),and j (x) as a function of human veins were also significant difference.