The paper analyzes the tendencies in demographic development of the municipality of Bosilegrad in the period from 1961 to 2011. For this purpose, it was necessary to determine the contribution of certain components of demographic development (natural and mechanical movement of the population) and to analyze them. The demographic development of the municipality is largely a reflection of the natural-geographic and economic-political circumstances (Lajić et al., 2010). The decrease in the total number of inhabitants was strongly influenced by emigration for decades, and also the negative natural increase contributed to the overall depopulation. The influence of natural movement and migration on population change and their relationship varied during the observed period. In the period from 1963 to 1991, total depopulation was taking place under the direct influence of the negative migration rate. In the same period, natural increase was positive but insufficient to compensate for the loss of population. In the last twenty years, the reduction in the number of inhabitants has been under the direct influence of negative natural increase. During this period, the intensity of migration has weakened, while the influence of natural increase prevailed..
