A warm-up apparatus GS for a fuel cell 1, 51 comprising: a compressor 22, 71 for feeding supply gas A to the fuel cell 1, 51; a main passage W1, W3 connecting the compressor 22, 71 and the fuel cell 1, 51 and feeding supply gas A; an intercooler 23, 73 arranged in the main passage W1, W3; and a bypass passage W2, W4 connecting the compressor 22, 71 and the fuel cell 1, 51 and feeding supply gas A in such a manner that the supply gas A bypasses the intercooler 23, 73.