Abstract: A fuel cell device may includes: a housing including a top panel and a plurality of side panels; a fuel cell module disposed in the housing, the fuel cell module housing a cell stack that carries out power generation by utilizing a fuel gas and an oxygen-containing gas; and a plurality of auxiliary machines that assist operation of the fuel cell module. A plurality of panels among the top panel and the plurality of side panels may serve as a maintenance panel that can be detached during maintenance or component replacement, and at least two panels among the top panel and the plurality of side panels do not serve as the maintenance panel.