Arsenic rock and sand,two main substances in Mu Us Desert,called“two evils by the locals an the primary causes of soil erosion and land desertification.This paper mainly focuses on the farmland-building technology of mixing arsenic rock and sand.It also studies the characteristics of mixed soil of arsenic anc sand in different proportions. The results showed that crops growing in Fuping County and Yuyang engineering demonstration zone had good effects,indicating that corn is suitable for planted in 1,2 remixed soil,anc the most suitable ratio for potato is 1,5.The soil fertility and environmental quality of mixed soil are botl in line with the planting standards.