Abstract: A pair of specific primer had been designed according to full length sequence of Potato leafroll virus coat protein gene (PLRV-CP) in the GenBank. Potato leafroll virus coat protein gene (PLRV-CP) had been cloned with the RNA of Potato leafroll virus as moplate, and plant expression vector had been constructed. PLRV-CP gene had been transformed to protoplate of the potato variety Daxiyang by the method of PLO (Poly-L-Ornithine) and transgenic plants. About 610bp interest DNA fragment had been amplification in 5 transgenic plants. This showed that exogenous PLRV-CP had been integrated to the genomy of potato. And the result of the Southern blot proved the correct of the PCR and the result of the RT-PCR further demonsticated that: there are positive expression in the 3 progenies of transgenic plants. And the potato leafroll virus inoculation experiment show that transgenic plants Resistant to the potato leafroll compared with control plants.