Selenium is one of the essential element to life which have close relations with human health. In order to expound the relation of Se in eco-environment with human body health, the distributional and differentia] rule of Se for each essential factors of eeo-environment in Shaanxi, the pathway and flux for trasmision of Se from environment to human body, the metabolism level of Se in our human body, and its effect on human body health has been studied systematically. It is showed that there are integrated eeo-environment series from deficiency-optimal-toxicity of Se in Shaanxi.The quaternary loess and granite with low-Se content are predominnted in rock and parent materials of the soil in Shaanxi, thus most of soil in whole province belong to the soil deficient in Se.