FUEL BATTERY

There is provided a fuel cell having excellent portability and transportability and exhibiting superior power generation efficiency for which it is possible to use a liquid or solid fuel, which has higher energy density than a gaseous fuel. A fuel cell includes an electrolyte (1), an anode (2) and a cathode (3) that are disposed so as to sandwich the electrolyte (1), and further includes a fuel supply portion that supplies a fuel to the anode (2), an oxidant supply portion that supplies an oxidant containing oxygen to the cathode (3), and a cell heating portion that heats the fuel cell, and the electrolyte (1) is made of a solid oxide, and the fuel is a liquid or solid at room temperature and normal pressure.