Abstract: The whole blood selenium content of the population is 0.009-0.020μ/ml according to 327 cases (5-60 years old) in 12 low selenium sites, and in 246 cases (5-15 years old) the content is 0.017 ± 0.008μg/ml (X ± S.D), which is the lowest selenium content seen in literature.In the normal selenium environment the whole blood selenium content of population is 0.053-0.091μg/ml according to 241 cases (5-50 years old) and 0.076 ± 0.017μg/ml (X±S.D) in 206 cases(5-15 years old).It is coincident with the literature value in low selenium regions in the world.The whole blood selenium content is in normal distribution.The whole blood selenium content of population in low selenium has the same critical value(0.020μg/ml) as Seresponsive disease in animals.The whole blood selenium content of 66,61% population is less than 0.020μg/ml.The whole blood selenium content is low in spring and high in summer in both selenium environments according to the seasonal dynamics.And the population are in poor state in lower selenium fenvironment.The whole blood content of the population who are fed with foreign commercial food is higher than that of the rural population fed with local food.The former does not suffer from kaschin-Beck disease.The selenium nutrition state of population in low selenium environment in China is strongly controlled by the selenium flux in the environment and low selenium nutrition is basic character.The rule of the temporal and spatial changes of population in selenium nutrition is Coincident with the ruel of epidemiology.The incidence is significantly in negative relation to the selenium content in human body.This is the typical Se-respounsive disease in human body.The authors suggested that the diseases related to low whole blood content according to some literature may be caused by some other diseases instead of the low selenium environment.