To generate buoyancy cycle natural energy in the sea and on the ground by generating buoyancy natural energy in water in an elongated water container and vertically standing two or more elongated water containers used for motive power.

In a state that water is contained also in an air container for containing an amount of water to a floatation stop position of the air container floating in the water container, when air is supplied from a lower opening of the air container, the water in the container is expelled (a phenomenon that air is lighter than water occurs). The inside of the air container from which water is expelled forms an air body and buoyancy is generated. The amount of water expelled opens an exhaust valve of the air container in which water exists above the air body rising above the floatation stop position. Energy for expelling the air body is provided by force by which an amount of water existing above the air container falls to the original position.