Map is the most important tool for cognizance in the field of geography and is the best instrument for presentation of geographic information. The study of ecology, in general, wich means the study of relationship between man and his environment, is only possible by means of maps. As a tool for ecology and manifest of human sovereignty over environment, the map has served political powers and authorities. Therefore, it can play a critical role in persuation of the policies and exercising the authority. The concept of power is not limited political power but rather includes all forms and classes of power in a community. Why the authorities use the map as a tool for exericising power and impersuation of their policies? This paper is designed and conducted to respond the above question. There fore, a theoritical- coceptual framework is presented in wich the relation between the power and map is studied: 1- Semiology, 2- Power and Context, 3- Dis course, 4- Power and Media, 5- Perceptual and cognitive Map. The main Theory of this paper is that the map plays a role in Journal of Geographical Sciences, Autumn & Winter 2006- Spring& Summer 2007, Vol.6, No.8& 9 14 exercising power and impersuation of policy, because it is a “sign”. Frome the ontology point of view, the sign does not mean the exact reflection of realities and geographic phenomena but, rather replacing the realities. From the critical point of view the map is not a neutral tool for transfer information, bat it depends on the interests, aims and willings of producers and interpration of users. And from the constructivism point of view, in addition to the above-mentioned facts, the map is a tool for canstrction of realities.