Abstract: Objective To investigate the change of methylation levels of the long interspersed nucleotide acids element-1（LINE-1） promotor by using bisulfite sequencing PCR（BSP） in peripheral plasma of hepatocellular carcinoma（HCC）. Methods BSP method was used to detect the methylation levels of the LINE-1 promotor in 67 plasma samples from 33 cases of HCC（HCC group）， 18 cases of cirrhosis（cirrhosis group） and 16 healthy volunteers（normal group）. Results The results of BSP showed that methylation levels of the LINE-1 promotor in patients with HCC were significantly lower than those in cirrhosis group and normal group（P＜0.05）. The receiveroperating characteristic curve analysis of methylation of some CpG sites（site 1, site 7, site 8） in the LINE-1 promotor revealed an important diagnostic efficacy for HCC， and the sensitivity and specificity of the site 1，site 7，site 8 were 80.0％ and 78.8％， 81.8％ and 71.4％， 82.9％ and 75.8％， respectively. Conclusion The promotor of LINE-1 has hypomethylation in HCC， and methylation of some CpG sites（site 1, site 7, site 8） in peripheral plasma may be important diagnostic efficacy for HCC.