The study exposes the evolutional picture of birth and mortality rates of Bessarbian population during the Tsarist rule. These two phenomena of natural movement in population are shown based on existing statistical information. After analyzing the demographic data, it was found that between the annexation of Bessarabia by the Russian Empire and the World War I the birth curve, continuously fluctuating, experienced an upward trend. Mortality presents different levels in both living environments of the province, the annual number of deaths always varying, in higher or lower proportions, but also gradually increasing.