Résumé dans la langue de publication, traduction non disponible A method of reducing a friction on a cruising body, a cruising body (Y) with reduced friction, and a method of and an apparatus for generating microbubbles for use in reduction of friction, aiming at reducing a frictional resistance with a small energy consumption to thereby enhance an overall energy efficiency and make readily practicable a measure of reducing a frictional at resistance. A mixed fluid containing bubbles and water is jetted rearwardly and obliquely away from the submerged surface (4) of the hull (1) into a boundary layer formed in the vicinity of the submerged surface (4) from fluid jetting nozzles (3) so that a kinetic energy of water having a great mass is utilized to inject bubbles more deeply into a desired bottom layer of the boundary layer than in the case where only bubbles are injected, for effective reduction of friction. (see diagramm 1 page 0)