We studied fertility indices of Iranian and non-Iranian populations which were covered by 23 Rays health houses. This cross-sectional study aimed to prove the effect of increasing number of non-Iranian immigrants on health indices of the area covered by Tehran university of medical sciences and health services, consequently giving attention to specific health programs. The data collection method was census of permanent residents of the villages by means of vital horoscopes. 8494 of 27611 persons were non-Iranian. Dependency ratio and natural growth rate was 75%, 1.14% in Iranians and 98%, 1.74% in non-Iranians, respectively. Mortality in non-Iranians was 1.24 times more than Iranians. General fertility rate in Iranians was 60 and in non-Iranians was 110 live births in 1000 women of child bearing age. Total fertility rate in Iranians was 1.73 and in non-Iranians 3.27 neonates for each woman. Age-specific fertility rates were absolutely higher in non-Iranians. Gross eproductive rate was 0.87 in Iranians and 1.59 in non-Iranians. Mean number of girls born by a non-Iranian mother will be double times of an Iranian mother (P<0.01). Modern contraceptive methods coverage was 70% in Iranian couples and less than 40% in non-Iranian couples. 96.94% of Iranian deliveries and 70.9% of non-Iranian deliveries were safe (P<0.01).