Abstract: Chitinase has been introduced into Potato by Agrobacterium mediated transformation and Protoplast direct transformation method and got 13 transformed plants, Among them,5 plants got 900 bp the Target bands and the gene has been introduced into the genome by PCR and Southern blotting method. The result of RT–PCR show that three of the 5 have expressed the chitinase and the experiment of disease resistance further indicate that this gene has expressed strongly in the leaves of the potato. The disease resistance of the transgenitic plants increases 30% higher than the control.