The aims of this article is to analyze development levels in 2006 and study effective causes and factors on inequality in urban places of East Azerbaijan Province. The method of the study is descriptive-analytical. At first, thirty-nine development indices and degree of development as well as ranking of the regions were determined by using factor analysis and HDI methods. Urban places of East Azerbaijan Province were categorized in three levels of developed, developing and less developed by using of cluster analysis. By using of coefficient of variation gap and regional inequality was specified. Then, regression relation was proposed in order to predicate effective factors contributed in development and prioritize of regions for investment and coordination of regional inequalities. Finally, effective causes and reasons for progress or reduce inequality in urban places of East Azerbaijan Province were explained briefly. Examining influence factors in inequality in temporal-locational area case study shows that influence approximately all factors in inequalities, but relative to the temporal-locational and the human nature show that influence one factor or some of the factors in inequalities. Therefore, in study and analysis inequality matters alike other humanity matters that complex nature should be to operate on systematically and all factors of study. Also due to inequality a relative, dynamic and normative concept, therefore inequality should be interpreted according to the temporal-locational, economical, social, cultural, political and ideological conditions; in other words, it should be interpreted within the structural framework of the related system.