The morbidity of viral hepatitis was epidemiologically analyzed and the etiological structure of severe and chronic viral hepatitis was studied in the Republic of Sakha (Yakutia). Acute viral hepatitis B, whose portion is 43.5%, was found to be of the key significance within the structure of acute viral hepatitis (AVH). Acute viral hepatitis C (with 4.7% in the AVH structure) is by far more rare. The latter is close to the value registered in other Russia's regions. Apart from the prevalence of viral hepatitis B (32.4%) an exceptionally high share of chronic hepatitis delta (24.5%) was established for the etiological structure of chronic viral hepatitis, which is a specificity of the discussed region. The epidemic situation in the Republic of Sakha (Yakutia) was stated to be linked with the mentioned extra dangerous diseases, which requires appropriate emergency measures with the prevention vaccination program against hepatitis B being a priority.