The modern dynamics of the urban population of Belarus differs from the total population dynamics trend. The total population size of Belarus decreased from 10.1 to 9.5 million or 6%, in the period from 1989 to 2009 years. The urban population increased from 6.2 to 6.7 million, or 8.2% in the same space of time. Groups of towns by population size differ in the character of population dynamics. Population growth is typical for small towns, because of administrative reforms – some urban-type settlements get status of town. The population of small towns has increased by 17.5% during the period of 1989-2009 years, large and medium cities – by 7% an average. Natural movement indicators of the urban population of Belarus have significant differentiation between classes of towns by population size. During the period of 1989-2009 years the highest birth and mortality rates were established in the small towns. The highest birth and the lowest mortality rates are typical for large cities. Higher values of fertility rates in large cities determines by higher level of socio-economic development and the continued migration to cities the XXI century. The higher fertility rates in small towns are due to two factors: the state-support of small business in this group of settlements and attracting young professionals to new enterprises in small towns. Natural increase of population is manifested in all classes of towns in Belarus during the period 1989-2010 years. The highest rates of natural increase are typical for large cities with population size over 100 thousand people. In general, the demographic revitalization is obtained in 46% of towns in Belarus. This process is based on the factors of natural and migratory population movement. Population is growing due to natural increase and migration inflow with an absolute predominance in the structure of migratory factor in every fifth town (21%). In 17 towns (15%) population is increasing due to the predominance of one positive factor with negative value of the second (Natural increase > Migratory outflow, Natural decrease < Migratory inflow). Population decline with the dominant role of migratory losses is typical for 64% of towns in Belarus (mainly small and medium).