A spectral colorimetric apparatus includes a housing which includes a side wall. An outer surface of the side wall is an adjustment surface capable of adjusting a position of a linear sensor by moving while attaching the linear sensor to the adjustment surface. The linear sensor is supported by the side wall of the housing while abutting on the adjustment surface and receives alight beam that is dispersed by a concave surface reflection type diffraction element and passes through an opening portion. The adjustment surface is parallel to a tangential line at a part of a Rowland circle of the concave surface reflection type diffraction element, through which a light beam received by the linear sensor passes.