A facile method to synthesis PS/Ag composite microspheres with high and uniform metal coverage was proposed in this article, therefore avoiding the modification of PS beads. First, polyvinylpyrrolidone (PVP)-capped Ag NPs with a narrow size distribution were obtained by the modified polyol process, and then the PVP-capped Ag NPs were successfully loaded on the PS beads by using a combined swelling-heteroaggregation (CSH) procedure. The size distribution of Ag NPs and the morphology of PS/Ag composite microspheres were investigated. The results show that well-dispersed and uniformly coated PS/Ag microspheres are obtained and the coverage of the Ag NPs can be controlled by changing the amount of Ag NPs.