Modeling is a modern concept that enables the audience to analyze and understand components. Policy making models can describe complexity of what happening in real world in a simple and conceivable form. These models are considered as tools for clarifying thinking about policies and each one examines this issue with a special approach and from a specific point of view. In this article, it is attempted to present the most prominent policy making models collected by library study method, their effective factors are identified and the combined model of policy making in Iran is obtained based on relationships between these factors by interpretive structural modeling method using views of the experts. The results illustrates that the Cost-benefit analysis, political currents in society, previous decisions and social influence and power are the most influential factors in policy making.