Potato SN1 is a new type of antimicrobial peptide. In this study，the full ORF of SN1 gene was isolated，and was sub-cloned in frame to the 3’-terminus of the ORF of Glutathione S-transferase（GST） in the prokaryotic expression vector pGEX-4T-1. This allowed the recombinant protein GST-SN1 to be highly expressed in cells of Escherichia coli. The recombinant protein GST-SN1 can be expressed in the form of inclusion bodies after induction by isopropyl-β-D- thiogalactoside. The protein GST-SN1 was solubilized, denatured, refolded, and purified. The results of antifungal assay in vitro showed that SN1 exerted obvious inhibition against the growth of phytopathogenic fungi, such as Rhizoctonia solani, and Bipolaris sorokiniana. SN1 gene may be useful for improving wheat resistances against the above pathogenic fungi.