Abstract: To provide a colored optical layer capable of forming a solar cell module excellent in the design, and the power generation efficiency and the weather resistance, a method for producing an optical layer, an optical layer-provided solar cell module, an outer wall material for building, and a building. An optical layer having a functional layer containing an inorganic pigment and a matrix in which the inorganic pigment is dispersed, to be disposed on the side of plane of incidence of sunlight from solar cells, wherein at least a part of the inorganic pigment is an inorganic pigment having a maximum near infrared reflectance in a near infrared region at a wavelength of from 780 to 1,500 nm of at least 50%, an average particle size of from 5.0 to 280.0 nm and a specific surface area of from 5.0 to 1,000 m2/g.