Abstract: To understand the dynamic collapse mechanism of a spherical shell under an unsymmetrical load distribution, a shaking table test on a single-layer spherical shell was conducted. The dynamic characteristics of the spherical shell, dynamic response (displacement, acceleration and strain, etc.) and failure process due to both small and strong earthquake actions were studied through three seismic waves. By the Explicit dynamic analysis method in ANSYS/ LS-DYNA, the collapse process and mechanism under unsymmetrical loading distributions were carried out for the testing models. The result shows that the nodes of collapse area are in the loading zone under the unsymmetrical load distribution. Central main ribs buckling caused the larger dynamic effect and led to the formation of partial collapse, which were expanded and eventually led the building to be collapsed. The numerical model is also proved to be reasonable by comparing the theoretical and experimental results.