The objective of the present invention is to provide a mobile electronic commerce system that is superior in safety and usability. The mobile electronic commerce system comprises an electronic wallet 100, supply sides 101, 102, 103, 104 and 105, and a service providing means 110 that is connected by communication means. The service providing means installs a program for an electronic ticket, an electronic payment card, or an electronic telephone card. The electronic wallet employs the installed card to obtain a product or a service or entrance permission. The settlement process is performed by the electronic wallet and the supply side via the communication means, and data obtained during the settlement process are managed by being transmitted to the service providing means at a specific time. A negotiable card can be easily obtained, and when the negotiable card is used the settlement process can be quickly and precisely performed.