A fuel oil atomizing agent solves the problem of difficult crude oil atomization when used in an oil field heating furnace which does not have associated gas and takes crude oil as fuel. The invention is characterized in that the atomizing agent comprises the following compositions in percentage by weight: (a) 20 to 25 percent of No. 200 solvent oil, (b) 2.0 to 3.0 percent of vanadic oxide, (c) 1.5 to 2.0 percent of barium oxide, (d) 20 to 30 percent of ethanol and (e) the balance being No. -10 diesel oil; moreover, the sum of the weight percent of the compositions is 100 percent. The fuel oil atomizing agent has the advantages that when the fuel oil atomizing agent prepared through adopting the method is added in fuel oil inside a fuel oil heating furnace at a multi-purpose station, fueloil atomizing property can be increased so as to ensure more complete combustion of fuel oil. When 0.01 to 0.3 weight percent of the fuel oil atomizing agent is added in the fuel oil, up-to-standard emission of flue gas generated by crude oil combustion can be realized, and more than 4 percent of fuel oil can be saved.