This thesis presents a simple ring antenna structure to operate for the 2.45GHz and 5.8GHz dual-band RFID. After designing the two bands initially, we observe the behavior of current in the antenna and adjust the size. Since this will affect the impedance matching, we have to adjust the shape to achieve load matching. Repeat the above steps several times to get the final design. The size of antenna is reduced simultaneously. Note that for such an RFID antenna, conjugate matching to the chip has also been considered to achieve good efficiency of power transmission.