The present study explores the demographic dynamics of the Naga population of Dimapur with respect to their population structure, fertility, and mortality along with other reproductive factors. Data have been collected from 460 Angami, 544 Ao and 573 Sumi women from 12 villages of Dimapur. Information on demographic profile, reproductive performances of mother, healthcare behavior and socio-economic features of the Nagas of Dimapur district were collected by using standard pre-tested semi-structure schedule. Results have shown that the sex-ratios of children (0-14 years) were lower than that of the reproductive ages. Moreover step-wise regression analysis shows that the present age of mother, age at marriage and age at conceptions are the statistically significant factors influencing fertility and mortality among Angamis, Sumis and Aos. An inverse relationship between fertility and education and economic status were observed in the present populations. Mortality status in these tribal groups is much reduced as compared to the present status in Nagaland and other states of India. An in-depth study with combined biological, socio-cultural and economic insights into their population structure is required for comprehensive understanding of demographic processes in this region.