A wind power generation device comprises a generating device and a rotating device. The generating device comprises a generator and a transmission shaft, and the rotating device comprises a central shaft, a rotating support rotating around the central shaft and at least two fan blades rotatably arranged on the rotating support and symmetrically distributed on two sides of the central shaft. One end of the central shaft is fixed, a gear groove is further arranged on the rotating support, and an angle adjusting device for changing the rotation angles of the fan blades is arranged in the gear groove. The wind power generation device utilizes the rotating support to drive the fan blades to revolve so as to convert wind energy into mechanical energy, can transmit the mechanical energy through meshing among gears, effectively improves the efficiency of wind power generation, and further is simple in structure and low in production cost and using cost.