For the crossflow filtration of colloidal suspension with porous media, the fluid permeates through the media, while the particles move toward the media surface. The critical permeate flux is influenced by the back transport associated with Brownian diffusion, lateral migration, shear-induced diffusion, and interaction-enhanced migration. We performed a series of experiments on the effect of interaction between the particles and the micro-pore wall by adopting the partial rejection with conditions of polydisperse Kaolin particles of 0.1-2.6 μm and average pore size of 0.4 μm. Above pH 3.3, both the particles and the pore wall are negatively charged, and the magnitude of zeta potential increases with increasing pH value. Many previous studies show that the critical permeate flux of the complete rejection notably increases with increasing zeta potential. An opposite behavior has been obtained in this study of the partial rejection, where the particles can favorably permeate the micropores. This is because that the stronger electrostatic repulsion hardly makes the particles permeate as pH increases, resulting in a development of the cake layer close to the pore entrance. The rejection data allow us to confirm this phenomenon, meaning that the long-range interaction between the particles and the pore wall essentially affects the critical permeate flux for the partial rejection.