This article analyses the distribution of causes of death in Barnaul between the second half of the 19th and early 20th centuries. The author studies the influence of various causes on the formation of the mortality situation among adult population (16–59 years). Referring to the database “The Population of Barnaul in the Second Half of the 18th — Early 20th Centuries Based on the Materials of Parish Books” the author analyses deaths of Orthodox believers of the Church of the Intercession between 1869 and 1911. About 60 % of deaths in the structure of male mortality (16–59 years) resulted from infectious and intestinal diseases. Deaths caused by tuberculosis in this group amounted to 35 %. In women, due to fewer deaths from tuberculosis (25.5 %), the rates of infectious diseases are lower. The percentage of deaths from intestinal infections is quite high: for women it was 10.9 %, for men — 7.6 %. The proportion of deaths from viral infections (smallpox, measles) and bacterial diseases (diphtheria, scarlet fever) is insignificant regardless of gender. External causes of death claimed the lives of adult men (11.7 %) four times more often than those of women (2.9 %). Mortality rates from respiratory diseases in women were 10.2 %. Women died 1.5 times more often than men (6.7 %) as a result of diseases of this group. A significant number of women of reproductive age died during pregnancy and because of birth complications (7.5 %). A large number of deaths were caused by exogenous diseases associated with exposure to the environment. However, endogenous diseases were not inexistent either (12.5 % of cases in men, 16.1 % in women).