The rectenna of 2.45G㎐ for low-input power is designed and implemented by voltage doubler structure and quasi yagi antenna. The rectenna uses schottky diode HSMS-2852 which is manufactured by Avagotechnology. It is difficult to match the impedance of antenna and that of rectifier to obtain maximum efficiency of conversion at low input power. Quasi yagi antenna is employed to get high gain and printed antenna, whose radiation pattern is endfire pattern. The simulation is conducted with ADS and HFSS and Designer. The conversion efficiency of the rectifier of the rectenna is about 32% when incident power received by the antenna of rectenna is 0dBm. The antenna of rectenna suppress the second order harmonic of fundamental frequency, whose gain is measured with 5.35dBi. The returnloss and operative bandwidth of antenna are respectively about 22dB and 510MHz.