A process of manufacturing a laminated packing material in which ascorbic acid and the like can bring out the best in functionality and which does not complicate the lamination operation of the laminated packing material and does not impair the lamination properties of the laminated packing material is provided. [Solution] The process of manufacturing the laminated packing material is a process of manufacturing a laminated packing material which has a polyolefin thermoplastic resin exterior layer, base material, coating supporting layer and polyolefin thermoplastic resin interior layer and is used for filling and packaging a fluid food, wherein an alcoholic solution of ascorbic acid or ascorbate is mixed with a coating formation solution consisting of a coating formation component and an evaporative coating formation adjuvant element to obtain an ascorbic acid containing coating solution, the ascorbic acid containing coating solution is applied to the surface of the coating supporting layer, and the alcoholic solvent and volatile coating formation adjuvant element are evaporated to form a coating in which small particles of crystalline ascorbic acid or ascorbate are dispersed uniformly.