During the deposition of particulate matter to form a porous medium, interlayers of different structures are usually formed due to factors such as sedimentation, gravitational sorting and fragmentation of coarse particles. The form of interlayer distribution has an important influence on the stress distribution, structural strength and deformation properties of porous media. However, existing structural parameters such as voidness, coordination number, and friction angle cannot fully characterise the effect of interlayers on the structural stability and contact anisotropy of porous media under stress. A discrete element method (DEM) was used to simulate the mechanical behavior of particles during compaction under triaxial stress servoing in a study on the structural stability of porous media interlayers. The mechanism of the influence of different interlayer parameters on the overall structure of porous media is revealed. The influence of the thickness and number of interlayers on the mechanical behavior and structural deformation of porous media is analysed according to the structural parameters of the formed porous media and the parameters of the interlayer particles. Based on the structural stability and stress anisotropy of porous media, the mechanical properties of the interlayer were found to have a particularly significant effect on the macroscopic strength and structural stability of porous media, taking into account the inter-particle contact force, contact direction, and volumetric strain correlations.