Abstract: This study derives an analytical solution for the scattering of plane waves from a cylindrical cavity in a half-space of unsaturated porous media, based on the wave function expansion method and the Hankel function integral transform. By introducing the Hankel transform, the orthogonality issue of boundary conditions at the half-space surface and cavity wall is effectively addressed, enabling accurate determination of surface displacements and cavity-induced stress responses. The effects of saturation, incident angle, frequency, and burial depth on wave propagation are systematically investigated, providing theoretical support for related analytical studies and engineering applications.