Based on the clerical sheets and confession records and administrative population registration data of Barnaul in the XIX century, the article analyzes the dynamics of the members of the military class as well as the reasons for the changes observed. The author has come to a conclusion that in the pre-reform period the sources mark the lack of clearly defined tendency in dynamics of absolute number of military which averaged 1000 people. The proportion of the military for a specified time did not change significantly in Barnaul though the clerical sources report the decrease in the share of the military in 1873 to 5.6 % which resulted from the disbanding of the Kolyvan- Voskresensk battalion in 1971. In the 1880–1890s the average indicators made 12 %. In 1864 — the end of the 1870s the administrative population registration data record the considerable increase in the share of military (with the maximum of 45.9 % in 1866). It resulted from the fact that the lower ranks of the workers at the Altai factories, after receiving the “retired” status by the reforms of the 1860s, were referred to the military class. In the 1880s they were distributed among other population classes which resulted in the drop of the military class proportion. However, the main reason for the decrease of indicators by the end of the XIX century is associated with the results of the military reform in 1874.