Abstract: In order to clarify the function of St NPR4 in potato,the CDS and promoter sequence of St NPR4 were cloned and bioinformatics analysis was conducted. Tissue expression pattern was performed by q RT-PCR,and a binary expression vector of St NPR4 driven by its own promoter was constructed and transformed intopotato. Transgenic plants were used to examine the responses to salicylic acid,Phytophthora infestans and highsalt stress respectively. The results showed that St NPR4 had typical functional domains in NPR1 family with cisacting elements on the promoter in response to biotic and abiotic stresses. The St NPR4 expression level washighest in leaves St NPR4 was inductively expressed by SA and the induced expression was higher in transgenicplants than in the control. St NPR4 transgenic potato plants showed enhanced resistance to Ph. infestans andhigher rooting rate under high salt stress. This indicated that St NPR4 played an important role not only in bioticstress but also in abiotic stress of potato.