Abstract:Potato virus X(PVX) was isolated and purified from infected tobacco leaves. The cDNA was synthesized with synthetic oligonucleotide as a primer and cloned into bluescript vector. The gene encoding coat protein of PVX was cloned with restriction enzyme analysis and DNA hybridization. The full length of DNA sequence of the gene was determined and compared with sequence reported before. It was found that the gene cloned from PVX infected in China has high homology in DNA sequence to that reported abroad. We transformed the coat protein, gene to potato plants and obtained potato shoots on selective medium.