To investigate the enhancement effect of polyurea coating on the blast-resistance ability of steel storage tanks, in this paper, two ground explosion experiments were carried out on the coated steel tanks with polyurea coating sprayed inside and uncoated steel tanks, and the response data such as displacement time history and residual deformation of the measuring point of the tanks were collected. Meanwhile, ALE fluid-structure coupling analysis method in LS-DYNA software was used to simulate the explosion response process of the tanks, and the influence of different coating connection settings and tank materials on the coating protection effect was investigated. The test results show that the inner spray polyurea coating can significantly reduce the maximum displacement and residual deformation of the tanks. The numerical simulation results show that the influence of different connection settings between the polyurea coating and the steel plate on the peak displacement of the tanks is negligible, while the influence on the residual displacement of the tanks is great. At the same time, with the increase of steel yield strength, the displacement reduction ratio of polyurea coating decreases gradually.