AIM: To investigate the viral and host causes of fatty liver in chronic hepatitis B patients and the role of fat deposits in liver damage. METHODS: A total of 164 patients (113 males and 51 females, average age 35±11.3 years, and range 10-62 years) with previously untreated chronic hepatitis B were included in the study. The patients were divided into two groups depending on the result of liver biopsy: group without steatosis (100 patients with <5% hepatosteatosis) and group with steatosis (64 patients with >5% hepatosteatosis). The groups were compared in terms of gender, body mass index (BMI), liver enzymes (ALT, AST, ALP, GGT), cholesterol, triglyceride, HBeAg, viral load, and histological findings. In the group with steatosis, the patients were subdivided depending on the degree of steatosis into mild group (45 patients with 5-24% steatosis), and severe group (19 patients with >25% steatosis). RESULTS: In the group of chronic hepatitis B with steatosis, the mean age, BMI, cholesterol, and triglyceride levels were significantly higher than those in the group without steatosis (P<0.05). Steatosis was found in 53 (46.9%) of male patients and 11 (22%) of female patients (P<0.05). No significant difference was found in the positivity of ALT, AST, ALP, GGT, HBeAg, viral load, histological activity index (HAI) and stage between the two groups (P>0.05). In the group with severe steatosis, the BMI was significantly higher than that in the group with mild steatosis (P<0.05). No significant difference was found in the other parameters between the groups (P>0.05). CONCLUSION: Steatosis in chronic hepatitis B appears to be a result of metabolic factors of the host rather than the effect of viruses. Steatosis is unrelated to the HAI and degree of fibrosis, which are considered as the histological indicators of liver damage. METHODS: A total of 164 patients (113 males and 51 females, average age 35 ± 11.3 years, and range 10-62 years) with previously untreated chronic hepatitis B were included in the study. The patients were divided into two groups depending on the result of liver biopsy: group without steatosis (100 patients with <5% hepatosteatosis) and group with steatosis (64 patients with> 5% hepatosteatosis. The groups were compared in terms of gender, body mass index (BMI), liver enzymes (ALT, AST, ALP, GGT), cholesterol, triglyceride, HBeAg, viral load, and histological findings. In the group with steatosis, the patients were subdivided depending on the degree of steatosis into mild group (45 patients with 5-24% steatosis), and severe group (19 patients with> 25% steatosis). RESULTS: In the group of chronic hepatitis B with steatosis, the mean age, BMI, choleste rol, and triglyceride levels were significantly higher than those in the group without steatosis (P <0.05). Steatosis was found in 53 (46.9%) of male patients and 11 (22%) of female patients The difference was found in the positivity of ALT, AST, ALP, GGT, HBeAg, viral load, histological activity index (HAI) and stage between the two groups (P> 0.05) than that in the group with mild steatosis (P <0.05). No significant difference was found in the other parameters between the groups (P> 0.05). CONCLUSION: Steatosis in chronic hepatitis B appears to be a result of metabolic factors of the host rather than the effect of viruses. Steatosis is unrelated to the HAI and degree of fibrosis, which are considered as the histological indicators of liver damage.