Abstract: In recent years , RFID has been quickly popularized and used in many service field like purchase,distribution ,commercial, manufacture ,logistics and other fields. The tasks and aims of RFID is providing the information ofindividuals, animals and goods. RFID system overcomes the problem that the label cannot store much information and cannotrewrite information. RFID system non-connect exchange information between data carrier and the reader. Accord to the methodhow the RFID system uses energy and change information. We called the non-connect identification system RFID system. Thereader reads information from data carrier by exchange energy. The common antennas used in RFID system are dipole antenna,yaugi-uda antenna, patch antenna, microstrip antenna and slot antenna.