A swimming pool skimming device, including a loophole for guiding the pool water, extending lengthwise from a water inlet front aperture of the loophole to a rear aperture of the loophole, a connection duct and a water filtration and discharge body connected to the rear aperture by the connection duct, the loophole including a first bottom wall, two first side walls (22, 23) for guiding the water which are connected to the first bottom wall, and a first upper wall connected to the two first side walls (22, 23) for guiding the water, the connection duct including a second bottom wall, two second side walls (62, 63) for guiding the water which are connected to the second bottom wall, and a second upper wall connected to the two second side walls (62, 63) for guiding the water, the water filtration and discharge body including at least a third lower side wall (52, 55) laterally delimiting a housing, the loophole being intended to be inserted into a housing hole provided in an upper portion of a fourth wall of the swimming pool, the first bottom wall of the loophole, the two first side walls (22, 23) for guiding the water of the loophole, the second bottom wall of the connection duct, the two second side walls (62, 63) for guiding the water of the connection duct and the third lower side wall (52, 55) of the water filtration and discharge body are made of a single first bottom part ending in a first upper edge, characterized in that the first upper wall of the loophole, the second upper wall of the connection duct and a third upper side wall of the water filtration and discharge body connected to the third lower side wall (52, 55) are made of a single second cover part, which is added and fixed onto the first upper edge of the first bottom part. the loophole including a first bottom wall, two first side walls (22, 23) for guiding the water which are connected to the first bottom wall, and a first upper wall connected to the two first side walls (22, 23) for guiding the water, the connection duct including a second bottom wall, two second side walls (62, 63) for guiding the water which are connected to the second bottom wall, and a second upper wall connected to the two second side walls (62, 63) for guiding the water, the water filtration and discharge body including at least a third lower side wall (52, 55) laterally delimiting a housing, the loophole being intended to be inserted into a housing hole provided in an upper portion of a fourth wall of the swimming pool, the first bottom wall of the loophole, the two first side walls (22, 23) for guiding the water of the loophole, the second bottom wall of the connection duct, the two second side walls (62, 63) for guiding the water of the connection duct and the third lower side wall (52, 55) of the water filtration and discharge body are made of a single first bottom part ending in a first upper edge, characterized in that the first upper wall of the loophole, the second upper wall of the connection duct and a third upper side wall of the water filtration and discharge body connected to the third lower side wall (52, 55) are made of a single second cover part, which is added and fixed onto the first upper edge of the first bottom part.