This furnace uses an imported burner. The hot high-temperature flue gas generated by combustion is directly mixed with the dry cold air sucked by the induced draft fan at the mouth of the fan to generate a hot air heating device that generates a high-temperature mixed gas (its thermal efficiency is close to 100%). Direct-fired gas-fired hot blast stove is easy to start, fast air heating speed, convenient operation and maintenance, output temperature adjustable between 60 ~ 240 ℃, can be used with various drying equipment. Can be widely used in sunflower seeds, peanuts, almonds, pecans, pistachios, green fruits and other food and tea, aquatic products, medicine, chemical, plastic coating, building materials, printing and dyeing and other fields of drying and baking operations.