To provide a transaction processor improved in service for a user who settles a transaction payment with value information stored in a non-contact medium having a radio communication function.

A transaction processor 1 instructs a card processor 2 to settle the transaction payment with value information as one of medium information stored in a non-contact IC card 5. When uncompleted processing occurs while settling the transaction payment with the value information stored in the non-contact IC card 5 by the card processor 2, the transaction processor 1 acquires a transaction log relating to the latest transaction stored in the non-contact IC card 5, and decides whether or not the latest transaction log is the current transaction log. When it is decided that the latest transaction log is the current transaction log, the transaction processor 1 processes the transaction so that the transaction payment is regarded to have been settled with the value information stored in the non-contact IC card 5 in spite of uncompleted processing.