The invention relates to a wave-power unit with a floating body (1) connected by flexible connection means (3) to a translator (6) reciprocating in a linear generator (2), The floating body (1) is arranged for floating on the sea and the stator (8) of the generator for anchoring on the sea bed, According to the invention the connection means is guided by a guiding device (9) through lower and upper openings, The part of the connection means (3) that momentary is within the guiding device (9) is thereby guided to be aligned with the translator movements adjacent the lower opening and to be allowed to be inclined adjacent the upper opening. The invention also relates to a use of the invented wave-power plant and to a method for producing electric energy.