A purge method for a fuel cell system, according to one embodiment of the present invention, for easily removing oxygen from the inside of a stack, comprises: a fuel supply reduction step of reducing the amount of fuel supplied to the stack of the fuel cell system; an air supply reduction step of reducing the amount of air supplied to the stack and preventing a discharge of air; a nitrogen charging step of charging the inside of the stack with nitrogen in the air, while consuming oxygen by loading; and a stopping step of stopping the supply of the fuel.
