The gene of human neurotrophin-3 (hNT3), a 380 bp fragment corresponding to a 14 kDa protein, was amplified by PCR with genome DNA of human whole blood as the template and cloned into a vector pTXB1. The recombinant including the hNT3 gene was expressed in E. coli and the target product was in the form of inclusion bodies. After denaturation and renaturation, the hNT3 was purified on an affinity column by a self-cleaving intein. The bioactivity assay showed that the purified hNT3 induced profuse neurite outgrowth from the dorsal root ganglia (DRG) explants.