Abstract: In a vacuum packaging machine having a forming station and an evacuation and sealing station, wherein each station has a chamber made of an upper and a lower part, and each part comprises a base portion (top cover or floor, as the case may be) and four upstanding walls, one or both of said chamber parts is made from material having an appropriate cross-sectional shape, preferably U-shaped, forming the base portion and opposite side walls, the front and rear walls being secured thereto in the form of covers. The cross-sectional shape may be double U-shaped, providing accommodation for connections for chamber supply requirements (vacuum, air, power). Also the cooling plate for the lower part is secured on the under-side of the floor of said part and mounts it on the means for imparting chamber opening and closing movement to the lower part, while the cooling plate for the upper part is inside the chamber, on the under-side of the top cover.