Objective: To construct the extracellular region of PCP-2(PCP-2EC) and the immunoglobin IgG Fc fusi on protein expression vector,and then express and purify the soluble PCP-2EC/Fc fusion protein for the study of its function in neuronal adhesion. Methods: PCP-2 extracellular region was amplified and cloned into an expression vector pIGplus containing human IgG Fc; PCP-2EC/Fc fusion protein was expressed by COS-7 and 293 cells transfected by the constructed plasmid and purified by protein A. The purified fusion protein was used as substrate to study its function in neuronal adhesion. Results: PCP2 extracellular region was cloned into IgG Fc expression vector successfully; PCP 2EC/Fc fusion protein was expressed and purified in mammal cells; and the purified fusion protein promoted neuronal adhesion. Conclusion:PCP 2EC/Fc fusion protein expression system is successfully constructed and the purified fusion protein can promote neuronal adhesion. These results lay a foundation for the research on the PCP-2 function in neuronal adhesion and the further functional study in the nervous system and other fields.