A kind of multi-purpose comburant was developed for various oil-fired furnaces. The comburant added in 0# diesel oil or DF-1000 heavy oil was tested separately on a diesel engine table, a dieselized truck, and a heating furnace. The test results show that the comburant has better comprehensive performances as the adding dose rate is 0.1%. And the average fuel saving rate of the comburant is above 2.5% for diesel oil, and above 5% for heavy oil. It can also reduce exhaust soot, carbon deposits, HC and CO emissions, etc.