An apparatus for manufacturing capsules under vacuum for preparing beverages, comprising: - a plurality of support elements arranged in sequence along a closed route having at least a rectilinear and horizontal operative tract, and - a driving system adapted to move said support elements along said closed route, advancing them into the operative tract according to a predetermined advancement direction and stopping them one at a time in a plurality of operative stations, wherein each support element comprises a row of housing seats which, at the operative tract of the closed route, are mutually aligned in a horizontal and transverse direction of alignment with respect to the advancement direction, wherein the operative stations are arranged above the operative tract of the closed route of support elements and comprise at least: - a loading station for inserting into the housing seats a glass-shaped body having mouthpiece directed upward, - a filling station, placed downstream of the loading station with respect to the advancement direction of the support elements, for filling glass-shaped bodies inserted in the housing seats with a food substance adapted to produce a beverage, - a covering station, placed downstream of the filling station with respect to the advancement station of support elements, for applying and fixing on the mouthpiece of glass-shaped bodies inserted in the housing seats a closing film, and - a sealing station, placed downstream of the covering station with respect to the advancement direction of support elements, for placing under vacuum the inner volume of the glass-shaped bodies placed in the housing seats and for sealing the closing film on the mouthpiece thereof, characterized in that said sealing station comprises: - a plurality of bell-shaped members arranged mutually placed side by side in a transverse direction with respect to the advancement direction of the support elements, each of which is adapted to overlay to one respective housing seat and has mouthpiece directed downward, - a movement apparatus for moving each bell-shaped member in vertical direction between a raised position, wherein its mouthpiece is substantially spaced apart from the support element, to a lowered position, wherein the mouthpiece thereof leans against the support element surrounding the correspondent housing seat, - a vacuum generating apparatus to reduce the pressure within the inner volume of bell-shaped members, and - a plurality of welding elements, each of which is contained inside a respective bell-shaped member for airtightly welding the closing film on the glass-shaped body contained in the housing seat. - a plurality of support elements arranged in sequence along a closed route having at least a rectilinear and horizontal operative tract, and - a driving system adapted to move said support elements along said closed route, advancing them into the operative tract according to a predetermined advancement direction and stopping them one at a time in a plurality of operative stations, - a loading station for inserting into the housing seats a glass-shaped body having mouthpiece directed upward, - a filling station, placed downstream of the loading station with respect to the advancement direction of the support elements, for filling glass-shaped bodies inserted in the housing seats with a food substance adapted to produce a beverage, - a covering station, placed downstream of the filling station with respect to the advancement station of support elements, for applying and fixing on the mouthpiece of glass-shaped bodies inserted in the housing seats a closing film, and - a sealing station, placed downstream of the covering station with respect to the advancement direction of support elements, for placing under vacuum the inner volume of the glass-shaped bodies placed in the housing seats and for sealing the closing film on the mouthpiece thereof, - a plurality of bell-shaped members arranged mutually placed side by side in a transverse direction with respect to the advancement direction of the support elements, each of which is adapted to overlay to one respective housing seat and has mouthpiece directed downward, - a movement apparatus for moving each bell-shaped member in vertical direction between a raised position, wherein its mouthpiece is substantially spaced apart from the support element, to a lowered position, wherein the mouthpiece thereof leans against the support element surrounding the correspondent housing seat, - a vacuum generating apparatus to reduce the pressure within the inner volume of bell-shaped members, and - a plurality of welding elements, each of which is contained inside a respective bell-shaped member for airtightly welding the closing film on the glass-shaped body contained in the housing seat.