The invention provides a photomask and a method for manufacturing the same. The method for manufacturing the photomask comprises forming a light-tight pattern layer on a substrate; forming a protecting layer covering the light-tight pattern layer and the substrate plate; and forming an antireflection layer covering the protecting layer. The refractive index of the protecting layer is larger than that of the antireflection layer. The problem that a substrate of an existing photomask reflects can be solved.