Abstract: Polystyrene macromer with a norbornene end group (PS-NB) was prepared by coup-ling polystyrene anion (PS^-) with 5-bromomethylnorbornene (BrMNB) in a mixed sol-vent of cyclohexane and tetrahydrofuran (THF).Molecular structure of the macromer was characterized by ^-H NMR,IR, and GPC methods. Investigation on the coupling reaction parameters showed that presence of polar solvent THF greatly improved coupling effi-ciency. Without additional separation procedure, pure PS-NB was able to be synthesized when volume fraction of THF was up to 10% and [BrMNB]/[FS^-] ratio up to 4.