A sensor storage container is provided that allows sensors to be checked visually from the outside. A container is used for storing sensors including an oxidation-reduction enzyme that oxidizes or reduces an object to be analyzed, a mediator that mediates the transfer of electrons caused by oxidation or reduction, and a detection means that detects the oxidation or reduction reaction. The container is transparent or semi-transparent in whole or in part and thereby the sensors can be checked visually from the outside of the container. This container may be composed of a container body and a lid. The container body may be provided with a scale. Preferably, the sensors are those produced using a ruthenium metal complex as the mediator.