A combustion-type exhaust gas treatment apparatus has a combustion treatment chamber for treating exhaust gas by combusting and decomposing the exhaust gas, a main burner for forming a flame in the combustion treatment chamber by supplying a mixture gas produced by premixing a fuel gas and an oxidizing gas, and a scraper for scraping off solid matters adhering to an inner wall of the combustion treatment chamber. The mixture gas is adjusted within combustion range and supplied to the main burner during treatment for treating the exhaust gas by combusting and decomposing the exhaust gas when the scraper is not in operation, and the mixture gas is adjusted outside combustion range and supplied to the main burner during treatment for treating the exhaust gas by combusting and decomposing the exhaust gas when the scraper is in scraping operation.