We reviewed the clinical data and hepatic histologic findings of 25 patients with the acquired immunodeficiency syndrome who underwent 29 liver biopsies. Our experience indicates that the only hepatic feature characteristic of acquired immunodeficiency syndrome is serologic evidence of exposure to the hepatitis B virus. The most common histologic finding was macrovesicular steatosis. Granulomas appeared in seven patients and were due to mycobacterial disease (3 patients), histoplasmosis (1 patient), adverse reaction to sulfonamide (2 patients) and unknown causes (1 patient). The clinical indication for liver biopsy was not significantly different in the patients without or with granulomas or with granulomas secondary to mycobacteria or fungi. Mycobacteria were cultured from all histologically positive specimens and one histologically negative specimen. Liver biopsy should be performed in any patient with acquired immunodeficiency syndrome who has unexplained fever, hepatomegaly or abnormal results of serum biochemical liver tests, and all specimens should be stained and cultured for mycobacteria and fungi.