The underground silos can take full advantages of the underground space, which is of better fireproof, anti-toxicity, explosion-proof and other merits. In the meantime, the underground silos can use the shallow geothermal energy to realize quasi-low temperature storage. With the advantages of energy-saving, low-consumption and grain quality-ensuring, it plays a significant role in ensuring the grain safety and sustainable development of China. The mechanical properties of the silo wall before completion acceptance of large underground concrete silos were studied by the combination of engineering full-scale test and numerical analysis. By comparing the test results with the engineering-scale testing results,, the rationality and effectiveness of the numerical analysis method were verified. Furthermore, the mechanical properties of the silo wall under the most unfavorable load conditions were numerically analyzed. The results show that the internal forces of the numerical simulation results of the silo wall were in good agreement with that of experimental results. Due to the relatively large thickness of the silo wall, and the rigidity of the contact part between the silo wall and the silo bottom and the silo roof, the radial stress on the inside and outside of the silo wall shows the opposite law. The radial stress of the silo wall is highest at the bottom of the silo wall, and the hoop stress is highest at about 2/3 of the position from the top of the silo wall. Under the most unfavorable load conditions, the radial stress and hoop stress of the silo wall show similar changes with the burial depth as in the actual working condition, and the stress is greater at the same depth.