Abstract: To reduce the complexity and computational cost of solving scattering fields with the exact 3D model, an approximate model of S0 Lamb wave scattering from a through hole in isotropic plates is presented by using Poisson plate theory for describing in-plane wave modes. The model makes use of the wave function expansion technique and the boundary conditions at the edge of hole to obtain the far scattering fields of S0 and SH0 modes. Compared to the exact 3D model, the obtained results of Poisson model show a good agreement with those of the 3D model at low frequency. The scattering characteristics of two fundamental guided wave modes for the holes of different sizes are also explored. It is found that the scattering wave amplitudes at some scattering angles change linearly with the hole diameter, which provides a quantitative basis for Lamb wave non-destructive evaluation.