The scientific understanding of migration and migrant's characteristics constitute the pivotal context for migration policy-makings and management.  Such an understanding in developing countries including Iran is mainly attained through population censuses. In Iran, in spite of long-term considerable migration movements from neighboring countries and its consequences, the demographic characteristics of foreign migrants still remained unexplained. Thus, this paper aims at investigating demographic characteristics of foreign migrants using existing data derived from 2006 Iranian census.

The research finding demonstrate that the high sex ratio, higher fertility rate than native population, young structure of population, large size of second generation migrants and geographical concentration  are among the most significant features of foreign migrants. It should be admitted that there is a significant difference among migrants groups. In addition, the results indicate that although the migrants are demographically different from that of their country of settlement, their population size is not so large to have considerable effect on Iranian population structure and dynamic.