Tracheal ventilation device, particularly a tracheal tube, which seals the trachea in a substantially air-tight manner. The device includes a cuff that blocks the trachea below the glottis and is traversed by a ventilation cannula. The cuff is larger in its filled, freely displaceable, unrestricted state than in its filled state positioned in the trachea. The cuff is of a flexible soft film material and lies against the trachea by means of its folds. The device is adapted to the morphology of a child's larynx and is available in finely graded sizes.