With the increasing spread of Internet and its application in various business processes and its profit by save time and reduce place limitations via the web, we observe the several forms of trade boom to take better. However this situation deals to variety of risks with their various forms. Some studies show that these risks create the negative attitude in users and they are the most important preventive factors in using e-commerce. The above factors caused complexity, challenge, ambiguous, and risk feeling in the customers who use of electronic capabilities. This paper analyzes the base researches in the theory of perceived risk and reviews the related research in the two major dimensions of e-commerce: "buying and selling products online and e-services". Also the study compares the findings with existence researches in Iran, as a developing countries. Consequently we identify a general classification of the risks and their effects in e-commerce.
