An improved suspension polymerization was carried out by using unsaturated polyester resin as monomer instead of styrene in the common used method. Suitable polyvinyl alcohol product was chosen as dispersant agent. The improved method has much more advantages compared with the common used method, such as the reaction time is less,the product has more average size of particles, the experiment succeeds in 100% and the cost is saved. Students show their very interest in this experiment. The good effect indicates that the improved experimental design can be used as the content of "polymer chemistry experiment for undergraduate students".