A spectroscopic sensor includes a wiring substrate having a main surface, a light detector disposed on the main surface of the wiring substrate, a Fabry-Perot interference filter, a spacer which is provided on the main surface of the wiring substrate and supports the Fabry-Perot interference filter so that the Fabry-Perot interference filter and the light detector are separated from each other, and a stem connected to a ground potential. A second current path which has a smaller electric resistance than that of an arbitrary first current path which extends from the Fabry-Perot interference filter to the light detector via the spacer and the wiring substrate is formed between the Fabry-Perot interference filter and the stem.