A heat insulating box of a refrigerator includes a non-flammable heat-insulator particularly a vacuum heat-insulator made of a board-shape molded inorganic fiber. Therewith non-flammability of the heat insulator is ensured and a refrigerator box prevented from catching an outside caused fire is achieved, thus a refrigerator which is safe even when a flammable refrigerant is used and which is high in energy-saving is provided.