Comparison of large groups of patients with acute viral hepatitis A (HA), B (HB) and non-A, non-B (HNANB) revealed that the highest percentage of anicteric forms is found in HA (44.8%) followed by HNANB (27.3%) and the lowest percentage in HB (23.6%). Investigation of mean values of biochemical functional liver tests showed that 1. the highest mean values of bilirubinaemia, ALT and AST were recorded in HB. The differences are statistically significantly higher (p less than 0.01) than in the two remaining types. 2. The difference between the cholesterol serum level, GMT and ALP in HB and HNANB on the one hand and HA on the other hand was at the same level of significance. 3. The transaminase activity is only slightly higher in HA than in HNANB, the differences are not significant (p greater than 0.05). 4. The cholestatic features are more marked in HNANB than in HA. The differences are also significant (p less than 0.01). In the clinical picture in acute HNANB symptoms of influenza predominated (53.33%), followed by digestive complaints (47.5%) and the percentage of articular complaints was lowest (24.17%). Analysis of 24 cases of fulminant forms of viral hepatitis revealed that this course was most frequent in HB (50%), followed by HNANB (41.7%) and least frequent in HA (8.3%).