A method for fabricating a wire grid polarizer according to an embodiment comprises: forming a conductive layer on a substrate; forming a guide layer on the conductive layer; forming a hard mask pattern to partially expose the guide layer; forming a guide pattern to partially expose the conductive layer; providing a block copolymer of two monomers having different etching rates; forming two sets of monomer blocks by aligning the block copolymer; selectively removing one set of monomer blocks; and forming a conductive wire pattern using the remaining set of monomer blocks and the guide pattern as etching masks. A width of an upper end of the guide pattern adjacent to the hard mask pattern is smaller than a width of a lower end adjacent to the conductive layer. The width of the upper end of the guide pattern is smaller than a width of the hard mask pattern.