To provide an air pressure accumulating structure utilizing wind force to compress air and utilizing it as a power source for useful energy for power generation.

A rotating shaft 30 extending to the vertical direction is rotatably installed on a base 1, and an arm 38 extends from the rotating shaft where a blade 31 is mounted. A windmill device 3 is formed at the lower end of the rotating shaft with an arm 36 extending from the rotating shaft where a roller 32 mounted. At the same time when the rotating shaft rotates with the blade on the windmill device receiving wind, the roller rotates around the rotating shaft, whereby a protruded body 13 on a piston 12 using an air chamber 10 as a cylinder is pushed down into the air chamber against an elastic body 14 and the piston is moved down in the air chamber. Thus, the air pressure accumulating structure is provided in which air in the air chamber is compressed and fed to an air storage tank 20.