At present, the complete system info about anti-floating design of the underground mass structure has not yet been formed, designers of underground circular grain silo often calculate it without considering the effect of the soil which is good for the silo anti-floating. Based on this, through theoretical analysis, considering the various factors which are good for anti-floating design, such as the wall friction with the soil function, cohesive force between silo bottom and soil, negative pressure possibly existing and so on, adopting the method of indoor simulation experiment, what can be got is that comprehensive reduction factor in dense sand soil can be adjusted to 0.40～0.45, using mathematical analysis for buoyancy reduction factor can be adjusted to 0.94, considering the favorable effect to warehouse of soil body, safety factor, which is based on anti-floating calculation structure on the basis of the principle of Archimedes, safety factor can be adjusted to 0.52, if not, it can be adjusted to 0.99.