To provide a technique capable of miniaturizing a housing structure for a button cell while protecting the button cell from the outside.

An opening 28 is formed on the back of a case body 20 in an electronic device 1. A battery housing section 27 for housing the button cell capable of being inserted from the opening 28 is arranged on the case body 20. A spacer 40 arranged on a gap between a protection seal pasted on the case body 20 so as to cover the opening 28 and the button cell in the battery housing section 27 is integrally formed on the case body 20.