Several changes at the age structure of the population cause an increase in the aging index and a decrease in the potential support ratio. According to the data of 2013, Turkey’s aging index is 45.9 and the potential support ratio is 5.6. Compared with the aging index of the member states of the European Union (11.3), Turkey has lower aging index but higher potential support ratio. Index values vary between cities. The aging index value is higher at the western and northern cities but lower at the eastern and south eastern cities of Turkey. The potential support ratio shows an opposite behaviour; while it is increasing at the eastern and south eastern cities, yet it is decreasing at the western cities. The Pearson Correlation test shows that there is a significant correlation between the aging index and the net migration rate. Also a positive correlation was determined between the potential support ratio and the decreasing of the population growth rate.