The utility model relates to a counterweight foundation block for a large-scale inflation film facility. The foundation block includes a mortise block and a tenon block, the mortise block and the tenon block are insertedly jointed via a protrusion and a groove that are mutually engaged, the tops of the mortise block and the tenon block are connected to an angle iron via a preset lower margin bolt and a nut, the two sides of the top surfaces of the mortise block and the tenon block are provided with longitudinal side displacement proofing holes, and drill rods are arranged in the longitudinal side displacement proofing holes; and one side of the mortise block and the tenon block is connected to a steel plate via a preset nut and a bolt. The beneficial effects of the utility model are that the foundation block provided effectively solves the structure of an inflation film, particularly the moving problem of the large-scale inflation film structure and facility, realizes the convenient detachment and installation during the moving of the inflation film structure and facility, and prevents a large amount of waste of manpower and material resources due to a one-piece foundation, so the foundation block provided is environment friendly in the process and has no secondary pollution; the foundation block provided ensures the repeated use of the facility and has lower requirements on the treatment of the substrate of the facility, therefore, the foundation block provided facilitates in the further development of the application field of the inflation film structure and facility.