In order to achieve an efficient collection of wave energy and stable power output, a two-float oscillating flapping-wing wave energy converter is proposed. Based on the hydraulic conversion system of the multi-chamber cylinder, a hydraulic conversion and merging system of the multi-chamber cylinder is created. The composition and working principle of the system, as well as the parameters of the acquisition mechanism, hydraulic conversion and merging system, are determined. AQWA is used to simulate the flapping-wing angular displacement response, and AMESim is used to build the simulation model of the acquisition mechanism, the hydraulic conversion and merging of multi-chamber cylinders, and the power conversion and energy storage system. The research results show that the system can work stably under level 3 and 4 sea conditions, and the input power of the battery is stable at about 46.5kW and 56.5kW, respectively. The rationality and feasibility of the two-float oscillating flapping-wing wave energy converter are verified by simulation.