The present invention relates to the technical field of display, in particular to a prism film, a method for manufacturing the prism film, and a liquid crystal display device. The prism film comprises a prism film substrate and a polarizing layer; an upper surface of the prism film substrate is a prism surface, a lower surface of the prism film substrate is a bonding surface; the polarizing layer is formed on the bonding surface of the prism film substrate. In such a manner, the poor attachment problems of attaching a polarizing sheet on a liquid crystal cell in the manufacturing technology of a liquid crystal panel can be avoided; meanwhile the problem of the polarizing sheet being scratched during assembling the liquid crystal panel in other processes can also be avoided.