Liver cancer is one of the leading causes of cancer death in Mongolia. Since 1982-1986 , when HCC became themost frequent cancer among the Mongolian population, the rate has been increasing continuously. In the period2000-2005 years 35.3%of all newly registered cancer cases were liver cancers, with an incidence rate of 51.3 per100,000 population. Compared to the previous 5 year period, the rate increased by 11%. The objective here was toanalyze hepatitis B (HBV) and C virus (HCV)-related HCC cases and to evaluate the possibility of tumor marker(AFP) testing for early detection in Mongolia. Sera from a total of 513 patients with chronic liver diseases, livercirrhosis and HCC were analyzed for liver function (ALAT, ASAT) and hepatitis virus markers (HBsAg, anti-HCV).Sera from 316 patients were also examined for alpha-fetoprotein (AFP) levels. The overall incidence of HBsAg oranti-HCV were very high ( 95.3%) among all patients. Some 33.5% (66/197) of patients with HCC were positive forHBsAg and 45.2% (89/197) for anti-HCV. Moreover, 17.3% ( 34/197) of HCC patients demonstrated co-infectionwith HBV and HCV. AFP levels were elevated in 4.6% (11/238) and 29.5% (23/78) of chronic hepatitis and cirrhosispatients, respectively. In HCC cases, 84.3% (166) of patients had increased level of AFP ranging from 32ng/ml tomore than 400 ng/ml. We conclude that HBV/HCV infection is the main factor related to development of HCC inMongolia and that testing for AFP serum levels is a useful tool for early detection and diagnosis.