A method for controlling a peripheral system (or a plurality of peripheral devices) and a fuel cell system using the same. The method includes: allocating an operation priority to the peripheral devices; storing information of the operation priority; and sequentially operating the peripheral devices by using electric energy stored in a small capacity electricity storage device according to the operation priority. The fuel cell system includes: the plurality of peripheral devices; an electricity storage device electrically connected with the peripheral devices; and a controller for sequentially operating the peripheral devices by using electric energy stored in the electricity storage device according to an operation priority.