Abstract: A noncontact reader/writer is disclosed which performs, at a high speed, a processing of communication, such as read or write, with a plurality of noncontact information carriers such as noncontact IC cards. A transmitting unit transmits signals, such as commands, to the respective kinds of noncontact information carriers. A memory stores information about at least one of the kinds of noncontact information carriers with which the noncontact reader/writer communicated. A control unit decides, based on the stored information, the priority of the kinds of noncontact information carries in the communication processing and performs a communication processing. The stored information includes the kinds of noncontact information carriers or the number of occurences of communication with the respective kinds of noncontact information carriers.