Provided is a radio frequency identification (RFID) tag. The RFID tags includes: a conductive layer and a conductive line disposed above and below an insulation layer, respectively; an antenna connected to one end of the conductive line; a resistor connected to the other end of the conductive line; a first conductive plate connected to the conductive line and constituting a first capacitor in conjunction with the conductive layer and the insulation layer; and a first sensing device connected between the conductive line and the conductive layer and having an impedance changed according to a sensing of a first target material.