The article has aimed to define, explain and Classify the term "Middle-Class" and then to analyse and examine the main problems of the Iranian Society within the perspective of political Sociology. In classifying and defining the "Middleclass", the main foci were its typology, function, role & Status. Mean while the major processes of the structural-functional changes of Iranian Society during and after the revolution have been reviewed briefly.The overall processes of the Socio-politico and economic changes are analysed at macro-level, i.e. via analytic-functional paradigm within the context of "Third World Middle-Class Revolutions". All the findings are reduced to a micro-level (Iranian Revolution) then.The whole discussions on the Social, political, Economic and cultural changes in Iranian society are made within, and based upon, the three major spheres of ideology, politics and economy.