An airtight configuration for keeping down the permeation of corrosive gas from silicone adhesive, and for preventing corrosive gas from entering the case.An electronic device mounted on vehicle. The electronic device has at least one of a portion connecting components, and a portion sealing the clearance or hole where exists in the electronic device.The at least one of the connection portion and the seal portion is constituted by using adhesive or sealant which has at least one of a function adsorbing corrosive gas and a function trapping corrosive gas with chemical reaction.A car-mounted electronic device characterized by reduced permeation of corrosive gas into a case and high reliability.