As human’s life is getting more complicated, the cities are developed; people’s life style experiences have changed. This causes man’s efforts to meet his daily needs get energized in a drastically high speed. This has enforced the presence of automobiles (personal or pubic) in individual’s and family’s life as a significant element which surely affects the overall development of one’s life. The negative effects of this phenomenon also cannot be neglected as in some countries of the world the number of people passing away because of car accidents surpasses the ones dying from deadly and lethal diseases. Considering the fact that Iran is accounted as one of the countries with highest number of lethal accidents around the globe, the present research aimed at studying the social factors affecting the occurrence of car accidents in Tehran, the capital of the country. The qualitative results of the study reveal that macro structural and managerial problems of the country in various aspects added to the injustice existing in the distribution of facilities and social necessities (e.g.: job, which causes the influx of millions people into and from Tehran daily) accompanied by the inappropriate and nonstandard roads and streets creates a lot of problems for the city and its residents. When this is enforced by the great number of automobiles moving in the city, social organization of the city moves to degeneration causing abnormality and lethal car accidents.It is clear that via employing long run plans, aiming at decentralization of the city, just distribution of the facilities, and changes in the macro structures and management of the country, in the strategic aspects might reduce social factors affecting the occurrence of car accidents leading to death in Tehran. In terms of short time application, wise management can discipline the present traffic regulations and supervise their implication so as to reduce the complications of these events negative effects of car accidents in the city. Some suggestions are as follows: continual supervision of regulations; presenting people and the police with information and trainings; enhancing social awareness, social vision, and the like.