A wave power plant for extracting energy from the wave movement of a water surface area, which wave power plant comprises a frame construction (1), in which at least two rotors (3, 3a) are journalled, and wherein each rotor (3, 3a) is suspended in the frame construction (1) to the effect that the water mill wheel (3) is able to rotate about a shaft which is, in the normal use position of the wave power plant, essentially horizontal and is retained in the frame construction (1), and wherein means are provided for maintaining each of the rotors (3, 3a) partially immersed into a water surface area. The wave power plant is floating and comprises at least two non-parallel rotor shafts on which at least one rotor (3, 3a) is arranged on each rotor shaft.