Nonstoichiometric silica with multi-active groups particles (NS-MAG particles) were first synthesized, and then added to the porous matrix of PSF to prepare a NS-MAG/PSF composite membrane through a phase inversion process. The optimum preparation conditions of NS-MAG particles were researched and determined. Then the permeation fluxes of NS-MAG/PSF membranes with different doping amount of NS-MAG particles were tested. NS-MAG/PSF membrane, SiO2/PSF membrane, and PSF membrane were prepared respectively. These membranes were characterized by testing the tensile strength and the permeation flux. The results show that doping NS-MAG particles can better enhance the tensile strength and permeation flux of PSF membrane.