Bicycle carrier, adapted to transport bicycles on a car sunroof, of a type comprising: - a raceway assembled, through a front support and a rear support, on a pair of sunroof bars,, applied to the car sunroof; - a side arm, oscillating around an axis (y), which is horizontal and parallel with the sunroof bars,; - catching means placed next to an upper end of the oscillating arm, characterized in that the catching means comprising a tightening element adapted to form an undercut, so that, by forcing a cylindrical part of the bicycle against the tightening element, the tightening element opens and, by elastically closing again, the cylindrical part remains blocked, the catching means further comprise: - a rotary support, assembled on an upper end of the arm and rotatable, with respect thereto, around an axis (y'), parallel with an oscillation axis (y) of the arm, in order to be correctly oriented with respect to the cylindrical part; - a rotary hook adapted to tighten the cylindrical part against the rotary support, the rotary hook comprising a cylindrical part, which is inserted in a cylindrical seat, obtained on the support, the cylindrical seat having the same axis (y') along which the support rotates, on the cylindrical part, also with axis (y'), a groove being obtained, which comprises a first section, of an helical shape, and a second section, of a rectilinear shape parallel with the axis (y'), inside the cylindrical seat of the support a pin being present, which engages the groove so that the axial sliding of the cylindrical part of the rotary hook with respect to the cylindrical seat of the support generates, in a sequence, the rotation of the hook, to align it with the support, and the tightening of the cylindrical part of the bicycle against the support. - a raceway assembled, through a front support and a rear support, on a pair of sunroof bars,, applied to the car sunroof; - a side arm, oscillating around an axis (y), which is horizontal and parallel with the sunroof bars,; - catching means placed next to an upper end of the oscillating arm, characterized in that the catching means comprising a tightening element adapted to form an undercut, so that, by forcing a cylindrical part of the bicycle against the tightening element, the tightening element opens and, by elastically closing again, the cylindrical part remains blocked, the catching means further comprise: - a rotary support, assembled on an upper end of the arm and rotatable, with respect thereto, around an axis (y'), parallel with an oscillation axis (y) of the arm, in order to be correctly oriented with respect to the cylindrical part; - a rotary hook adapted to tighten the cylindrical part against the rotary support, the rotary hook comprising a cylindrical part, which is inserted in a cylindrical seat, obtained on the support, the cylindrical seat having the same axis (y') along which the support rotates, on the cylindrical part, also with axis (y'), a groove being obtained, which comprises a first section, of an helical shape, and a second section, of a rectilinear shape parallel with the axis (y'), inside the cylindrical seat of the support a pin being present, which engages the groove so that the axial sliding of the cylindrical part of the rotary hook with respect to the cylindrical seat of the support generates, in a sequence, the rotation of the hook, to align it with the support, and the tightening of the cylindrical part of the bicycle against the support. - a rotary support, assembled on an upper end of the arm and rotatable, with respect thereto, around an axis (y'), parallel with an oscillation axis (y) of the arm, in order to be correctly oriented with respect to the cylindrical part; - a rotary hook adapted to tighten the cylindrical part against the rotary support, the rotary hook comprising a cylindrical part, which is inserted in a cylindrical seat, obtained on the support, the cylindrical seat having the same axis (y') along which the support rotates, on the cylindrical part, also with axis (y'), a groove being obtained, which comprises a first section, of an helical shape, and a second section, of a rectilinear shape parallel with the axis (y'), inside the cylindrical seat of the support a pin being present, which engages the groove so that the axial sliding of the cylindrical part of the rotary hook with respect to the cylindrical seat of the support generates, in a sequence, the rotation of the hook, to align it with the support, and the tightening of the cylindrical part of the bicycle against the support.