IN-VEHICLE FUEL CELL SYSTEM FOR MOUNTAIN IN A VEHICLE

An in-vehicle fuel cell system, including a fuel cell, and an auxiliary machine configured to exchange a gas with the fuel cell, the in-vehicle fuel system including an auxiliary machine structure configured to accommodate the auxiliary machine, wherein the fuel cell includes a first fuel cell fixed to an upper surface of the auxiliary machine structure and a second fuel cell fixed to a lower surface of the auxiliary machine structure, the auxiliary machine structure is disposed at substantially the same position in a height direction as a skeleton member of a vehicle body, and the first fuel cell and the second fuel cell are fixed to the skeleton member via the auxiliary machine structure.