Demographic and Socioeconomic factors related to the urbanization of Iran are discussed. An historical review of the growth of urbanization in Iran is reported. Factors included in the analysis are the birth, death, literacy, and mobility rates as well as the age-sex structure of the population. The data are from the national censuses of 1956 and 1966. Changes in demographic trends in both major and smaller cities during this decade are discussed in detail. The results of the analyses of these data are applicable to most developing countries. This information may be of possible aid in planning for the growth and redistribution of the Iranian population.