A non-destructive method is used to measure the emitted degrees of the diffuse light along the small intestine meridian and surrounding non-meridian tissue. The attenuation of the diffuse light was analyzed at different time within a day. The experimental results revealed that intensity of the diffuse light decay following the exponential decay law with the 808nm light wave as probe when propagating along the small intestine meridian or non-meridian direction, existing the statistical feature in attenuation. Due to the temporal variation of the difference of attenuation of diffuse light, the rate of decay along the small intestine meridian is up to the highest at 12:00, being in accord with the blood running time of the small intestine meridian. This kind of experiment offered the reference to the Qi-blood transportation and the existence of human meridians.