To provide an incinerator and an incineration method suitable for incinerating the dead body of a pet capable of reducing easily a temperature of hot gas to about 200°C or less, and capable of clearing easily a regulation for the incinerator by a law, when discharging the hot gas from a combustion zone, from a stack (gas cooling tower) to an outside.

This incinerator/incineration method is provided with a primary combustion zone equipped with a burner for burning an incinerated object such as the dead body of an animal, a secondary combustion zone equipped in an upper side of the primary combustion zone, the gas cooling tower (stack) provided in an exhaust side of the secondary combustion zone to discharge the gas from the secondary combustion zone, and an atmospheric air intake port provided in a midway portion of a flow passage for guiding the hot gas from the secondary combustion zone to the gas cooling tower (stack), and for taking the atmospheric air for reducing temperature of the hot gas in from the outside.