A data transfer apparatus receives comparison data to be compared with stored data from an external unit, searches data corresponding to the comparison data from among the stored data, and transfers the searched data to the external unit. A control unit generates comparison-condition information for searching predetermined stored data from a data storing memory. A comparison-data storing unit stores the received comparison data. A comparison-condition storing unit stores the generated comparison-condition information. A transfer processing unit transfers the searched stored-data to the external unit.