To explore a new approach of expression of ABP-CM4 in methylotrophic yeast P. pastoris. The gene of ABP-CM4 was cloned into the vector pPIC9. The Sac I -linearized plasmid pPIC9-CM4 was transformed into P. pastoris GS115 by electroporation. By means of MM and MD plates and PCR, the recombinant P. pastoris strains (his- mut+) were obtained. Antibacterial assay, Tricine-SDS-PAGE and Polyarylamide Gel Electrophoresis demonstrated that ABP-CM4 was extracellularly expressed in P. pastoris with the induction of methanol. The recombinant ABP-CM4 has the antifungal activity on Aspergillus niger and Trichoderma viride.