Abstract: Through the long-term detection of Inner Mongolia Hongqinghe coal mine product warehouse in prestressed steel strand prestress,anddraw lessons from code for design of concrete structures and highway bridge rules in JTG D62-2004 which focus on the bridge of the prestress loss ,we were obtained the calculation formula of the large diameter prestressed concrete silo long-term prestress loss,and severally reached the theoretical value and the experimental value. Through the comparative method between the theoretical value and the experimental value, it is concluded that the formula of the rules is applicable to the silo and safer, at the same time, according to the measured data can be analyzed that the rules of the prestress loss of large diameter silo changes along with the passage of time and proportion of long-term loss in total loss.