Abstract: A wave pump activated by a wave energy for conveying a water to a desired place. The wave pump includes a tiltable hollow piston tube having an upper portion and a lower portion. The lower portion is communicated with a submerged pipe and the upper portion extends vertically upward toward a water surface. A piston portion is formed at an outer periphery of the hollow piston tube, and a cylinder which defines a cylinder chamber above the piston portion is fitted over the piston portion such that the cylinder can slide up and down. The cylinder is equipped with a float for moving the cylinder up and down such that a flow of water is generated in the hollow piston tube and submerged pipe.