Objective:To study the risk factors for spontaneous rupture of primary hepatic carcinoma. Methods :The clinical data of 31 patients with spontaneous rupture of primary hepatic cancer admitted to our hospital from Jan 1999 to Dec. 2008 were retrospectively analyzed, and compared with 31 randomly selected concurrent patients without rapture of HCC. Results:Three factors were shown to be the risk factors for spontaneous rupture of primary hepatic carcinoma.Those were APTT,HBeAg and the greatest height of tumor protrusion above the surface of liver. Conclusions:APTT,HBeAg and the greatest height of tumor protrusion above the surface of liver are risk factors for spontaneous rupture of primary hepatic carcinoma.