To prevent the adhesion of carbon, etc., which is produced when oil is burnt to the gas nozzle of an igniter for burning both oil and gas provided with an oil nozzle and the gas nozzle.

In an igniter device for burning both oil and gas provided with an oil nozzle 14 and a gas nozzle 15, an air passage 7 for supplying atomizing air to the oil nozzle 14, a gas passage 10 for supplying a gas to the gas nozzle 15, and a by-pass passage 11 which connects the air passages 7 and 10 to each other are provided. When oil is ejected from the oil nozzle 14, part of the atomizing air from the air passage 7 is guided to the gas passage 10 side through the by-pass passage 10 and blown out from the gas nozzle 15.