Abstract: To investigate the prevalent genotype of HCV in Lanzhou region,Polymeres chain reaction was used to detedct genotype in ser a from 83 patients with viral hepatitis C.841.4%(70/83)patients were able to type,of whom 48.57%(34/70)were genotype Ⅰ,45.71(32/70)were genotype Ⅱ and 5.72%(4/70)were mixed genotype Ⅰ and Ⅱ,genotype Ⅱ and Ⅲ were not detected. The more prevalent genotype of HCV were Ⅰ and Ⅱ,they were no significent difference.