The invention relates to a floating paddlewheel aerator for aerating water or clearing basins. Said paddlewheel aerator comprises a frame (1) of elongated floats (2, 3), said floats being substantially arranged at a right angle and being linked with each other in a T or H configuration. On a first float (2) further floats (3) or sections of floats are mounted on both its opposites ends. Said first float (2), on its top that is turned upwards by 90° compared to its lateral sides on which the further floats/float sections (3) are mounted, carries a drive unit (9). Said drive unit (9) is mounted entirely or partially on the floats and its output shaft (10) projects on both sides and parallel to the longitudinal extension of the further floats/float sections (3). Paddles (22) are disposed on the output shaft (10) and in the operational state of the aerator, when the floats float on the surface of the water or clearing basin, the shaft rotates above the level of the water or clearing basin and sections of the co-rotating paddles are immersed in the liquid.