Abstract: This paper summarizes the methods commonly used in the strength and stability design of buried oil tanks in China and carries out the calculation of wall thickness, check of stability, setup of reinforcing ring and the calculation of its size. In order to verify the theoretical design of its reliability and accurately find out the deformation and stress distribution of buried oil tanks, the model of oil tank and its surrounding soil is built by using ANSYS software and introduced into FLAC3D to conduct numerical simulation. Comparison on the theoretical design and the numerical simulation results shows that the theoretical design of oil tank is safe and reliable, but the design is too conservative, which leads to the low utilization ratio of the steel strength. The tank wall without reinforcing ring can meet the requirements of stability and the stability design methods and formulas are too conservative. The strength of head and stiffness of non-reinforcing ring oil tank is higher than the cylinder, and the stress and deformation increase from the two-heads to the middle part of the tank and the distribution of them on the whole tank is not balanced. The oil tank with reinforcing ring has a better mechanical performance because of the even distribution of stress and deformation.