To reduce the amount of smoke released into the atmospheric air from a stack down to zero or significantly.

A cylindrical combustion exhaust discharge section 3 is provided at a top part of the body 2 of an incinerator. A large-diameter part 11 is provided at a lower end part of a stack 4 and is mounted on the outer circumference side of a combustion exhaust discharge section 3. An outside air intake part 12 is formed between the combustion exhaust discharge section 3 and the large-diameter part 11 to introduce outside air into the stack 4. A re- combustion member 13 forming a metal screen is installed on the combustion exhaust discharge section 3. When combustibles are burned in the body 2 of the incinerator, the combustion heat heats the re-combustion member 13. As air is supplied onto the perimeter of the re-combustion member 13 through the outside air intake part 12, a combustion exhaust from the body 2 of the incinerator is re-burned when passing through the re-combustion member 13. This enables significantly reducing of the amount of smoke released into the atmospheric air from the stack 4.