Sex and age were determined in a skeletal sample from an 18th to early 19th century cemetery at Krivoshchekovo, a rural center since the mid-1790s. Historical records mention the area as the Krivoshchekovo Ob region. The village was founded by immigrants from European Russia. Archival sources concerning the demography of Krivoshchekovo were analyzed, mortality tables were constructed, proportions of various age groups were calculated, and average age of death was estimated for adults. Limitations of the study stem from the fact that the population of Krivoshchekovo was not stationary. The results of the paleodemographic analysis are compared with information from two archival sources: confessional lists and parish registers of St. Nicholas Church, where births, marriages, and deaths were recorded over the period from 1763–1841. Comparative material relates to Russian old residents and the local Tatar population of the Omsk Irtysh region in the 1600s–1800s. Sex and age were estimated in a skeletal sample of 462 individuals—one third of the number of deaths during 1763–1841, when people were buried at the graveyard. Child mortality was lower than among old residents, immigrants, or natives of the Middle Irtysh. The most vulnerable group in the Krivoshchekovo population were young women and children aged 1–4. The findings of the skeletal study agree with those derived from archival sources, and likely mirror the real situation.