Abstract: A device is constructed to convert wave energy to drive an output shaft in rotation. The output shaft can be connected to a nautical vehicle propulsion system or to a power generation system. A float rides upon the undulating surface of a body of water and is connected by a float lever arm which extends radially from a rocker shaft that is rotatably mounted in a frame located on a vessel or platform on a body of water. The rocker shaft undergoes reciprocating arcuate movement in response to movement of the float upon the undulating water surface. A pair of unidirectional clutch mechanisms are coupled to the rocker shaft and to a drive shaft which is also rotatably mounted on the frame. The unidirectional clutches are alternatively connected to turn the drive shaft in a single direction of rotation responsive to movement of the rocker shaft in both directions of rotation.