Expansion and development of social security and overcoming sickness, aging, unemployment, poverty risks and so on have always been a strategic goal and also a long – term strategy for all communities and governments in the world. This aim is a powerful instrument for making security, stability and social equity. For reaching to this purpose First should be setting the quantitative and qualitative objectives and compare those with macro structure of economical, social, cultural and political systems of each country. Even though in Iran has been made many efforts for social security system development in the last fifty years and this development also protect great number of urban workers, but this trend has not been compatible with basics of social security systems like comprehensiveness, sufficiency and universality for Iran's new society. For above reasons and with attention to deep economical and social changes, especially movements from centralized economical to decentralized economical structure (Market Economy), should be review conformity between social security systems with market economy factors. Of course breach of market economy regulations will give cause for imbalance between social security fund's incomes and outcomes and reduces social security services level in long term which is against basic human needs. This article has been studied relations between social security system (social insurance and social protection) and economical structure for scientific analysis of social security role in Iran's economy