A new design of dual-band radio frequency identification (RFID) printed antenna fed by a coplanar waveguide (CPW) is proposed, which operates in both 2.45 GHz and 5.80 GHz RFID bands. Its two measured impedance bandwidths are 32.0% at 2.45 GHz and 9.8% at 5.80 GHz respectively. The antenna has a simple structure sized 40 mm×40 mm, which is easy to be integrated with active devices and monolithic microwave integrated circuits. Details of the proposed antenna design and the measured results are presented and discussed.