Research was conducted for porous parameter inversion based on irregular acoustic incidence model to address the limitation of normal incidence case. A theoretical model was established for relating material porous parame- ters to the irregular incidence absorption coefficient. The acoustic response of porous materials under irregular incidence case was simulated to obtain the reference absorption data. The inversion study was conducted by using the established theoretical model and genetic algorithm, and the accuracy and astringency of inversed parameters was further analyzed. Results show a good agreement between theoretical and simulated outcomes and demonstrate high accuracy and astringency with relative errors of the inversed parameters below 9.0% and relative standard deviations less than 1 × 10?3. This study provides a novel theoretical approach for porous parameter inversion that presents considerable potential for both academic research and engineering applications.