To provide a business promotion system that reduces burdens on business participants and a site manager, while being appealing to customers.

The business promotion system uses prize providing information based on a computer system that includes a prize provider's terminal 60, companies' terminals 10 using the attraction of customers based on the prize providing information, customer terminals 30 using the prize providing information, and a management server 20 having an electronic mall. The management server 20 includes a prize group registration managing process means M81 for receiving the prize providing information and setting the information as prize group information; a prize providing information registering process means M82 for registering the prize group information in the management server 20; a prize competition participation managing process means M83 that matches a group of prize providing information; and a shop opening managing process means M85 for permitting requests from the companies' terminals to open shops at a mall site and for reporting the closure of the shops after the management server gives advance notice of the closure of mall services to the companies' terminals 10, to make the companies close the shops in the electronic mall.