The invention provides a heat-shielding material and window glass. The heat-shielding material comprising the following: a substrate; a metal-particle-containing layer that contains hexagonal or circular flat metal particles; and a low-refractive-index layer, the refractive index of which is less than or equal to 1.45. The principal surfaces of at least 50% of the flat metal particles form angles of 0 DEG to +-30 DEG with one surface of the metal-particle-containing layer. When installed on window glass, this heat-shielding material is oriented such that the low-refractive-index layer is the outermost surface on the indoor side. This heat-shielding material excels in terms of heat-blocking performance, visible-light transmittance, and resistance to light-caused degradation.