An electronic commerce system and an electronic commerce method for conducting electronic commerce making good use of characteristics of a mobile terminal. A mobile terminal provides authorization for a mobile commerce agent (MCA) to conduct electronic commerce for the terminal and notifies the MCA of information on the authorization. A commerce server notifies the MCA of information as to procedures for the electronic commerce. The MCA, at which the line of the mobile terminal may terminate, stores the electronic commerce procedure information received from the commerce server and the authorization information received from the mobile terminal. In response to a request from the mobile terminal, the MCA carries out the procedures for the electronic commerce which the MCA has the authorization to conduct according to the authorization information received from the mobile terminal based on the electronic commerce procedure information.