This paper presents a novel efficient charge pump composed of low Vth metal_oxide_semiconductor (MOS) field effect transistors (FET) in the course of realizing radio frequency (RF) energy AC/DC conversion. The novel structure eliminates tho se defects caused by typical Schottky_diode charge pumps, which are dependent on specific processes and inconsistent in quality between different product batche s. Our analyses indicate that an easy_fabricated, stable and efficient RF energy AC/DC charge pump can be conveniently implemented through reasonably configurin g the MOS transistor aspect ratio, and other design parameters such as capacit ance, multiplying stages to meet various demands on performance.