The following article is to investigate the social security of Qajar era as one of the major historic issues on the grounds of developments of the aforementioned dynasty and to cast light on the external and internal reasons that have brought up such disruption and to figure out what factors have been at play to form its concept? Based on historical data analysis, social security can be held responsible for socio-economic improvement which has acted as a contributing factor linking individual security as well as the national one. In Qajar era, the most significant threat posed at social security of that period of time as a community which has been the traditional epitome of safety, takes root in internal reasons (biological pattern, Eco-economic crises, tribal political constructure and it’ s associated culture, diminishing of governments responsibilities to securing the borders in the mainstream’ s idea, the lack of development in military institutions for providing security, the dominance of traditional approach to security the cities i. e. gates and thresholds ) and external means (Iran & Russia ’ s Tsar wars, Iran & England‘ s disputes over Harat, heightened influence of big powers in Iran‘ s socio-political affairs) on account of analytical-historical patterns, the findings of this research show that the concept of social security in constitutional era by the passage of time and the introduction of new concepts such as pursuit of law, social rights, the establishment of new military and judicial institutions, the growth of city dwelling and the betterment of education and it’ s citizen’ s understanding of urban rights was empowered to an extent and the social elites decided to change the political social and educational infrastructure with a view to a better improvement in national-individual and social security. The newborn constitutional system along with the development of urban social institutions and empowering of public setting made an attempt to facilitate the development process in the concept of social security.