A fuel cell device includes: a reformer that generates a reformed gas; a fuel cell; a combustor that combusts off-gas of the reformed gas and air for power generation, and generates a combustion exhaust gas; a first air heat exchanger that has a combustion exhaust gas path and a first air supply path, and that performs heat exchange between the combustion exhaust gas and the air for power generation; a fuel cell storage which stores the fuel cell; a second air heat exchanger that has a second air supply path that supplies the air for power generation to the fuel cell, and that performs heat exchange between the off-gas of the air for power generation and the air for power generation; and a housing that stores members. The first air supply path and the second air supply path are disposed to cover whole members stored in the housing.