A gas supply system according to the present invention comprises a gas filter disposed in a gas supply flow passage through which a gas is supplied to a semiconductor manufacturing apparatus and a metal component remover disposed in the gas supply flow passage downstream relative to the gas filter, which removes a volatile metal component contained in the gas flowing through the gas supply flow passage by liquefying the volatile metal component. The structure adopted in the gas supply system prevents entry of the volatile metal component, which cannot be eliminated through the gas filter, into the semiconductor manufacturing apparatus as the corrosive gas is supplied thereto by the gas supply flow passage.