Abstract: Principle, characteristics and technological process of changing steam-injection oil-burning boiler into burning hot gas boiler are introduced.Taking the changing case in Jinma Steam-injection Station in Liaohe Oilfield as an example, economic effectiveness for the improved steam-injection boiler is calculated.Results show that the technology of changing steam-injection oil-burning boiler into burning hot gas has the advantages of safety and high efficiency and is in favour of energy saving and environmental protection with notable social and economic benefits.