To provide a communication system that allows to more quickly execute communication with an RFID tag as a communication target even when there are a plurality of the RFID tags.

When a reader/writer 5 reads out ID information of a plurality of tags 3 while executing communication with a tag 4 by using a carrier wave of a vertically polarized wave, it individually executes communication with the tag 3, designated as the communication target on the basis of the ID information, by using a carrier wave of a horizontally polarized wave.