This thesis studies the Radio-frequency identification Front-End Integration research, measuring the value of circuit, study performance improving method. This circuit made by using the TSMC 0.18μm CMOS process. In order to reduce the transistor turn-on voltage, use Native NMOSFET instead of Triple-Well NMOSFET, This paper examines the characteristics of Native NMOSFET. Measured backward scattering modulator also proposed improvement program in addition. Finally, design two kind of transformer which can work on 915MHz and 2.4GHz, expect to improve the efficiency of energy storage structure.