Abstract: Dynamic response of a three-dimensional (3D) spherical cavity in elastic half-space under incident plane SV waves is investigated by using the indirect boundary integral equation method (IBIEM). The accuracy of the method is verified through comparison with the solutions in literatures. Taking a spherical cavity as an example, both the dynamic surface displacement and the dynamic stress concentration around the cavity in a homogeneous half-space are solved and analyzed through parametric studies, and the comparison between 3D and 2D results is implemented. It is shown that the dynamic responses around 2D and 3D cavity are similar in general, but there are still evident differences in wave-pattern conversion, especially for their peak values and spatial distributions, and the differences of the spatial distribution are more obvious when the incident frequency increases. In the anti-plane direction, the scattering effect is significant in 3D case, but it is difficult to be described in 2D case.