Policy making is a process that is particular nature and special form in different countries. The nature of policy making system depends on political, economic, social and cultural features. Success or failure of the policy making system in achieving its goal will determine within a cycle of the above factors. In this paper, our main question is why Iran’s policy making system is inefficient. This paper tries to analyze affecting factors in inefficiency of Iran’s policy making system by document method. These factors include non-coherent legal system, unfavorable political structure, multiple social cleavages, inappropriate cultural context, rentier economy and finally lack of discipline policy.