Due to the output voltage characteristics of the photovoltaic cell and other renewable energy generation systems, DC/DC converter with high step-up ratio is commonly needed to raise the voltage. The high gain Boost converter based on coupled inductor with switch capacitor network is presented in this paper. The proposed converter avoid the ultimate duty cycle by designing the ratio of the coupling inductor. As the energy of leakage inductor in the input side can be transferred to the output side, the loss of leakage inductor is reduced. The voltage peak of the switch is inhibited by the switching capacitor, which greatly reduces the voltage stress of the switch, thus the converter improves the transfer efficiency. The working state of the converter is analyzed in detail, the theoretical formula is derived, and the stress of the converter is analyzed in the paper. A simulation circuit is built to verify the theoretical analysis.