The present invention relates to a light laminated acoustic absorption sheet. The light laminated acoustic absorption sheet with flame retardant is characterized in that one or more thermoplastic fibers (a) having a low melting point and selected from polyethylene, polypropylene, polyvinyl chloride, polyester, polyethylene-polyester copolymers, and one or more polyester interlaced-textured yarns or thermoplastic hollow fibers (b) having a higher melting point than the thermoplastic fiber (a) and selected from polyester, polyethylene, nylon, hot-meltable fluororesin are mixed and opened so as to prepare a mat, and two or more sheets of mats are laminated by using an apparatus of manufacturing a stampable sheet so as to manufacture the laminated sheet, and then the laminated sheet is impregnated with flame retardant liquid.