The present paper aims at studying the internal factors affecting ethnic and national identity among Arab people of Ahwaz using quantitative method and survey technique. The sample of this study was 384 male and female Arabs aging 18 to 65 years old. In order to have a more precise study, a pretest questionnaire was given to 52 Arab people of Ahwaz. The final questionnaire was given to the sample during autumn and winter of 2006. The theoretical framework of this study is based on modernization, relative deprivation and internal exploitation theories. In this study, the effect of age, sex, marital status, employment, family income, the rate of family ownership, relative deprivation feeling in economic dimension, urban residence, neighborhood (Arab dominant or mixed),the rate of ethnic trust, abiding by ethnic norms, education, using media, satisfaction with political system, participation in political issues and relative deprivation feeling in political dimension were measured by ethnic identity variable. Finally, the relationship between ethnic identity variable and national identity variable was tested among samples. The result of bivariate analysis (T test, variance analysis and simple regression) revealed that above mentioned variable except 3 variables including sex, marital status and urban residence record were significant. Ethnic identity and national identity are significant negative relationship. The results of multivariate regression analysis revealed that 11 out of 16 independent variables affected ethnic identity which finaly explained 67 percent of ethnic identity variance.