National identity is a subjective sense of belonging to a specific national group, which is accompanied by a complex set of cognitions and emotions that express one attitudes towards this  group and other national groups.This study aims to study the social  and cultural factors related to national identity among over 15 year old citizes of Eghlid by the theory of  Castells as theoretical framework. The  method of this study was quantitative survey with questionnaire. 400 young people (over 15 year old) in Eghlid city by multistage cluster sampling were elected and were analyzed. The validity of questionnaire by face validity were obtained and reliability of research was verified by Cronbach's Alpha.Base on findings among 8  hypotheses in the study, 7 hypotheses were verified. Multivariate regression has shown that rate of religiosity (22 percent), age (6  percent), the communicative network expansion (5 percent) and rate of using media (3  percent) have explained 36  percent of the variations of dependent variable (national identity).