A fuel cell system with which excessive supply or supply shortage of a vaporized fuel is able to be avoided and stable power generation with high output is able to be made, and an electronic device using the same. In a vaporization chamber, a projection is provided as a heat conduction section to conduct heat generated in a power generation section to a liquid fuel supplied to the vaporization chamber. Between the end of the projection and an inner wall face of an inner member, a gap is provided. In the gap, the heat is effectively conducted to the liquid fuel supplied from the end of a fuel supply route, and the liquid fuel is vaporized. It is possible that the projection is contacted with a section in the vicinity of the end section of the fuel supply route in the inner wall face of the inner member, and thereby heat of the power generation section is conducted to the inner member through the projection, heat is conducted to the liquid fuel through the inner member, and the liquid fuel is vaporized. Thereby, it is possible to limit a target region to be heated according to the position of the projection, or to control the amount of heat conducted to the liquid fuel according to the size of the projection.