The purpose of this paper is understanding the feature of HBV genovariation from HB patients in Qingdao and discussing the influence of HBV YMDD variation and genotyping on cellular immunity level. The research method is to detect peripheral blood T lymphocyte subsets by flow cytometry (FCM), using enzyme-linked immunosorbent assay (ELISA) to detect serum cytokine interferon (IFN-g), tumor necrosis factor (TNF-a) and interleukin 2 (IL – 2)] level, applying  real-time fluorescent polymerase chain reaction (PCR) technique in serum detection of gene mutation, HBV DNA quantitative monitoring and detection of genotyping of 820 cases of hepatitis b patients and making a direct sequencing of PCR product .The result is that 154 cases of YMDD variation in 820 patients with HBV infection was detected and the variation rate is18.78%; the  YMDD variation difference between different genotyping was statistically significant, P“ÿ0ÿ05 and HBeAg positive people are more likely to variate; the difference of YMDD variation between  different genotyping of HBV infected person clinical genotyping was statistically significant(P“ÿ0ÿ05), among which LC(36/113)0CHB(97/368) is primary; difference of gender,age and DNA capacity from different group was not statistically significant(Pÿ0ÿ05), then select 91 cases of chronic hepatitis b patients, 19 cases was Leu60Val mutation and variation rate was 20.9% , fulminant hepatitis grouphighest was the highest with the mutation rates increase gradually; leval of Val60 IFN -g and TNF -a level mutant group was obviously increasing(t is 2.584; 4.766,P<0.01), ratio of CD4+/CD81 went up(t=2.275, P<0.05). Conclusion is that: Va16O variants may increase affinity with human I leucocyte antigen (HLA – I) affinity or raise the expression of HLA- I molecules – or to activate a lot of cytotoxic T releasing lymphocyte cytokine and at the same time exerting immunological effect in part of liver which improve the lethality to the host. Monitoring of HBV YMDD mutation has important clinical significance to treatment, prognosis and vest of HB patient.