A fuel cell system without a high pressure line of a hydrogen supplying system, including a gas charging line formed between a gas charging station and a high pressure vessel charged with gas by the gas charging station, and a gas supplying line formed between the high pressure vessel and a stack, includes: a regulator provided in the gas supplying line; a solenoid valve provided in the gas supplying line between the regulator and the high pressure vessel; and a check valve provided in a bypass line connecting one point of the gas supplying line between the regulator and the solenoid valve and one point of the gas charging line.