Abstract: Pipeline is a big energy consumption in oil transportation and heat medium heater is one of the major energy consumption equipment in oil transportation enterprise. After detail analysis and comparison to reasons on efficiency difference of heat medium heater's heat excergy and a series of energy saving measures using excergy balance theory, the article puts forward that rising oxygen concentration of combustion -supporting air to a certain extent will increase burning speed, raise flame temperature, reduce burning and heat excergy loss so as to increase heat medium heater's heat excergy and achieve the goal of energy saving.