Introduction For few decades, the population of cities in developing countries, including Iran had a higher growth rate than the total growth rate of countries' population.The cities in the developing countries have become areas of very high vulnerability to natural hazards such as earthquake. Analysis of urban density using statistical data has a crucial role in the urban geographic studies and urban planning. Based on studying type urban density can be measured by different models. While in developed countries, the development of the big cities began centuries ago and generally allows for controlled and planned urban density, the opposite is the case in developing countries, where rapid urbanization's process is characterized by an unplanned urban density. The developing metropolitan cities have enormous difficulties in coping both with the natural population increase and the urban physical expansion. In fact, urbanization process increases the vulnerability through centralization of human and property. Because of unplanned urbanization, growth of land in vulnerable areas with a high level of hazard risk, inadequate urban management and unsuitable construction measures, third world cities transform into vulnerable centers. density in metropolitan such as Isfahan, beside growing population , without caring to economic, social, spatial, aesthetic and the other urban planning effects, has created many conflicts so has drown the urban planners attentions.