This paper proposes a scalable dual-input high-gain DC/DC converter to meet the needs of photovoltaic panel integrated confluence in photovoltaic power generation systems. The converter adopts a novel topological structure, one which can achieve high-gain conversion of input and output voltages while reducing the voltage stress of the switching device. In addition, the proposed converter has scalability, which can extend the ports according to the number of photovoltaic cell panels and output voltage requirements, thereby reducing the complexity and cost of the system. This paper first introduces the topological structure of the proposed converter in detail, and deduces its operating principle in different operating modes. Then it conducts an in-depth theoretical analysis of the gain characteristics of the converter, the voltage and current stress of the switching devices, the parameter selection of key devices, and loss calculation. Finally, an experimental prototype with an output power of 1 kW is built and tested. The experimental results verify the correctness and feasibility of the theoretical analysis of the proposed converter.