By utilizing the fuzzy analytic hierarchy process and considering the mutual influence of the influencing factors on the trapping mechanism of diesel particulate filter, a complex interconnected evaluation system was decomposed into several independent hierarchical systems, and a comprehensive evaluation model of the trapping mechanism of diesel particulate filter was established. The results showed that the wall thickness, the porosity and the pore aperture were the most remarkable influencing factors to the main trapping mechanism. While the hole density, the diameter and the length were the secondary influence factors to the main trapping mechanism. The factor of porosity was overwhelmingly dominant to the diffusion mechanism, accounting for nearly 60% influence proportion; the pore aperture was the most important factor to the inertia collision mechanism, accounting for nearly 39% influence proportion; and furthermore, the porosity and the pore aperture were the equally important influencing factors to the intercept mechanism, the two accounting for 60% influence proportion.