To provide a stable high life time to prevent the quality degradation of a product such as an epitaxial wafer by keeping hydrogen chloride gas that liquefied hydrogen chloride is evaporated highly pure when evaporating the liquefied hydrogen chloride in a cylinder without reducing the pressure thereof in two stages, even if the supply amount of the liquefied hydrogen chloride in the cylinder fluctuates and the remaining amount of the liquefied hydrogen chloride stored in the cylinder is reduced.

Liquefied hydrogen chloride 12 stored in a cylinder 11 is evaporated and supplied into semiconductor manufacturing processes. A warming means, which consists of one or both of a temperature controller 16 mounted on the outer face of the cylinder in opposition to the liquefied hydrogen chloride stored in the cylinder and a temperature control device 28 provided in a cylinder installation chamber, warms the cylinder, and a controller 19 controls the warming means to warm the cylinder in accordance with the detection output of a temperature sensor 17 which detects an outer face temperature of the cylinder.