The invention discloses a preparation filling machine, which comprises a frame, on which a film-applying station, a heat-sealing station, a filling station, a sealing station, a modification station and an output station are successively installed. A film drawing station is also installed, and a preheating station for preheating and softening the two layers of the soft film is installed before the heat sealing station, and the heat sealing station also includes a preheating station for softening the two layers of the soft film The deformation device is a deformation device that exerts a mutually deviating force on the middle parts of the soft membranes to expand and deform the middle parts of the two layers of soft membranes outward. The soft film is softened by the preheating station, and the deformation device of the heat sealing station exerts force on the softened soft film to make the soft film expand and form, which can obtain a larger cavity volume than the natural state molding, and accommodate More liquid medicine, to a certain extent, increases the volume per unit area of the membrane material, improves the utilization rate of the material, and reduces the production cost.