Based on the scanning electron microscopy (SEM) image of polytetrafluoroethylene (PTFE) microporous membrane filtration material, the micro-structure model of PTFE filtration material was established, and the coupling method of computational fluid dynamics and discrete element method (CFD?DEM) was used to simulate the deposition of the viscous particles on the surface of microporous membrane. In addition, the force of the particles in the calculation domain was calculated by introducing the liquid bridge force model and without considering the effect of Van der Waals force. Then the deposition characteristics of 3~6 ?m particles on the surface of microporous membrane at different surface energies were analyzed, the simulation results were compared with the empirical formula of adhesion efficiency. The results showed that the relative errors between adhesion efficiency and empirical value, the force of particles and liquid bridge force model were less than 6%, which indicated that the CFD?DEM coupling method can be used to simulate particle deposition under different environmental relative humidity conditions. Filtration velocity, particle size and viscosity were important factors affecting the deposition morphology. When the filtration velocity, particle size and viscosity increased, the particles were more likely to form a stable dendritic structure on the surface of the filter material, which made the adhesion efficiency and dust-containing pressure drop increased. The environmental relative humidity affected the volume of liquid bridge between two objects, and the contact force affects the deposition of particles. With the increase of the surface energy and liquid bridge volume, contact force and liquid bridge force increased correspondingly. The environmental relative humidity had a great influence on the deposition of particles, according to the principle of force balance.