Circulating free cell DNA (cfDNA) is extracellular fragmentation of nucleic acids that occurs both in plasma and serum. This kind of DNA which derived from the apoptotic/necrotic cells or the lysis of circulating tumor cells (CTCs) can be detectedin the patients with a variety of diseases. Emerging evidence suggests that cfDNA from patients exhibits characteristicchanges of tumors, suchas mutations, insertions/deletions, methylations,microsatellite aberrations, and copy number variations, etc. All of these reveal a visible difference between the benign conditions, and thus may be useful in the diagnosis of cancer, identification of targeted therapy, monitor responses to treatments, and early detection of relapse. The purpose for this study is to explore these characteristic changes in the patients withhepatocellular carcinoma (HCC) and expect to guide targeted therapy and identify non-invasive biomarkers of cancer diagnosis and prognosis which can be easily isolated from the circulation.