Provided is an information management system that comprises: a payment information confirmation device which is connected over a network to a cryptocurrency system management terminal that manages a cryptocurrency system, which extracts transaction information including address information for a seller account in a cryptocurrency system, and which generates and transmits payment confirmation information including at least a transfer amount from the extracted transaction information; and a register device which is connected to the payment information confirmation device, receives the payment confirmation information from the payment information confirmation device, displays the received payment confirmation information, converts the currency units of an entered transaction amount into a cryptocurrency units payment amount in the currency units of the cryptocurrency system, generates a two-dimensional code in which are recorded the cryptocurrency units payment amount and the address information, and displays the generated two-dimensional code.