This paper introduces a cascaded high step up converter realized with a tightly coupled three-winding coupled inductor. Compared with existing high step up conver1 ters, the proposed converter features that the smaller the turns ratio is, the larger the conversion gain is. So, the name couple inductorreverse is given to represent reverse coupled inductor principle of operation. In addition, diode-capacitor circuit is introduced to not only recycle leakage energy to output, but also further lift voltage conversion gain. This paper illustrates operation principle of the proposed converter, discusses effect of leakage inductance on voltage gain, and deduces voltage and current stresses of components. Finally, a prototype rated at 400W has been established, and experimental results verify correctness of the above theoretical analysis.