A spectrometer comprising: a light detection element having a substrate made of a semiconductor material, a light passing part provided in the substrate, and a light detection part put in the substrate; a support having a base wall part opposing the light detection element through a space between the light passing part and the light detection part, and side wall parts (32, 33) integrally formed with the base wall part, the light detection element being fixed to the side wall parts, the support being provided with a wiring electrically connected to the light detection part; and a dispersive part provided on a first surface of the base wall part on a side of the space and configured to disperse and reflect light passing through the light passing part to the light detection part in the space, wherein a first end part of the wiring on a side of the light detection part is connected to a terminal provided in the light detection element, and a second end part of the wiring on an opposite side from the side of the light detection part is positioned on a surface of the support on an opposite side from the side of the space, wherein, by the first end part being provided on an end surface of the side wall parts (32, 33) and being connected to the terminal provided in the light detection element, the light detection element is fixed to the side wall parts (32, 33) so as to oppose the first surface of the base wall part, and by the light detection element being fixed to the side wall parts (32, 33), the space with an optical path from the light passing part to the light detection part and the electrical connection of the wiring to the light detection part is provided. a light detection element having a substrate made of a semiconductor material, a light passing part provided in the substrate, and a light detection part put in the substrate; a support having a base wall part opposing the light detection element through a space between the light passing part and the light detection part, and side wall parts (32, 33) integrally formed with the base wall part, the light detection element being fixed to the side wall parts, the support being provided with a wiring electrically connected to the light detection part; and a dispersive part provided on a first surface of the base wall part on a side of the space and configured to disperse and reflect light passing through the light passing part to the light detection part in the space, wherein a first end part of the wiring on a side of the light detection part is connected to a terminal provided in the light detection element, and a second end part of the wiring on an opposite side from the side of the light detection part is positioned on a surface of the support on an opposite side from the side of the space, wherein, by the first end part being provided on an end surface of the side wall parts (32, 33) and being connected to the terminal provided in the light detection element, the light detection element is fixed to the side wall parts (32, 33) so as to oppose the first surface of the base wall part, and by the light detection element being fixed to the side wall parts (32, 33), the space with an optical path from the light passing part to the light detection part and the electrical connection of the wiring to the light detection part is provided.