Objective To study the correlation between the drug-resistance variation and the genotypes of hepatitis B virus (HBV)detected by the PCR-reverse dot blot and the relation between the HBV variation loci with the liver function indexes and HBV DNA viral loading.Methods The serum samples from 462 patients with chronic hepatitis B treated by oral nucleoside drugs were screened.The PCR-reverse dot blot was adopted to detect the drug-resistance gene mutation loci and genotypes.The correla-tion between the HBV drug-resistance mutant with the genotypes,liver function indexes and HBV DNA viral loads was performed. Results Among 462 patients taking nucleoside drugs for treating chronic hepatitis B,45 drug-resistance mutants were detected with the mutation rate of 9.74%;in which,16 cases (35.5%)were 180M and 204I/V mutant,6 cases(13.3%)were 204V,13 ca-ses(28.9%)were 204I mutant,3 cases (6.7%)were 180V mutant and 3 cases(6.7%)were 236T mutant.The HBV genotyping showed 105 cases of genotype B,337 cases of genotype C,0 case of genotype D and 2 cases of other genotypes.Conclusion (1)The HBVgenotypes in Maoming area may be different from the genotypes in other southern regions and is dominated by HBV-C geno-type.(2)The PCR-reverse dot blot method is a detection method for fastly and accurately finding the drug-resistance loci after nu-cleosides therapy.(3)The clinical analysis demonstrates that the drug-resistance mutation loci has no correlation with the liver func-tion index ALT(P >0.05),but there was certain correlation between the drug-resistance mutation loci in hepatitis B and HBV DNA viral load(P <0.05).