Maintaining and strengthening national unity and integrity is one of the most important priorities of all political systems, because increasing the correlation coefficient can lead to reducing internal and external threats and providing good grounds for development and progress of the country. Iran is one of the countries that by relying on its historical background and civilization can overcome on the divergence challenges, throughout centuries. So despite, the occupation of this country and abstraction of some parts of vast territory by aliens at some historical sections, in recent decades,it continued to be a powerful and independent political unit with pervasive sovereignty. National unity and solidarity have been more exposed to domestic challenges and external threats and among them, the most important domestic challenge is the activation of some social gaps at some profiles of time. This article inevitably focuses on the role of external threats in weakening national unity on domestic factors and tries to investigate the ratio of four major social gap in Iran (generation gap, gender, ethnic and religious gap)with different dimensions of national unity (religious, territorial, political, cultural, social dimensions). The used method in this article is secondary analysis method of research findings and studied period is between 2001-2011. The obtained results show that in this time period, there is no serious disagreement between two ends of spectrums oriented to social gaps about the various aspects of national unity and national convergence in Iran has benefited from a good level.