A capacitance operation device includes an operation plate, an electrode, and an electrode film. The operation plate has an operation surface to be contact-operated by an operation body. The electrode outputs a detection signal according to a change in capacitance generated between the electrode and the operation body. The electrode film supports the electrode. The operation plate has a rear surface on a side opposite to the operation surface. The rear surface is formed with a groove. The groove is filled with an adhesive agent, and the electrode film is adhered to the operation plate with the adhesive agent.