Apparatus and method for preparing laminated nano-composite material. The apparatus comprising: a plasticizing-and-feeding device assembly consisting of n plasticizing-and-feeding devices; a current collector having n inlets, one outlet and a conjunction runner; k laminated composite generators connected in series, wherein each generator comprises one melt inlet channel, m branch laminated runners and one melt outlet channel, while the vicinity of each melt inlet channel is provided with m distributary openings, and each branch laminated runner can make each equal composite melt that flows out from each distributary opening rotate approximately 90 degrees and extend in width as it flows forward, and then join together and form a laminated structure melt, and the laminated structure melt which joins together at the melt outlet channel of the last laminated composite generator has n×mk layers; and a forming device connected in series to the melt outlet channel of the last generator.