In this paper, circling of the soil Se was studied by sampling the input endmembers of soil Se, such as atmospheric deposition, irrigation water and chemical fertilizer, as well as the output endmembers such as the harvested plant parts and soil seepage water, as the further study based on the multi-purpose geochemical survey (MPGS). Three aspects were found as the following: in general, the study area has a low soil Se level with the area of soil Se deficiency and potential deficiency covering 35.20% of the whole area; the maximum soil Se input comes from the wet and dry atmospheric deposition, and the maximum soil Se output endmember is the soil seepage water; soil Se in the study area shows a state of net accumulation, and the area of Se deficiency and potential deficiency will decrease from 35.20% to 31.7% in 20 years.