To provide a closed switchboard which eliminates the need for increase in the installation area, even when a plurality of systems of power supplies are used.

In the closed switchboard 1, an upper horizontal bus 11 is fitted to an upper section in its body 2, and a lower horizontal bus 12 is fitted to a lower section. A front-side vertical bus 15 is connected to the upper horizontal bus 11 from the front side of the body 2, and a rear-side vertical bus 16 is connected to the lower horizontal bus 12. A device housing chamber 4, mounted on the front side of the body 2, is supplied with power through the front-side vertical bus 15 and a device housing chamber 4 mounted on the rear side is supplied with power in another system via the rear-side vertical bus 16, by connecting the upper horizontal bus 11 and lower horizontal bus 12 to external power supplies in different systems.