Disclosed is a method of synthesizing Fe powders having sizes of tens of nm by vaporizing an iron atom-containing liquid material with a low melting point at high temperatures, and then condensing iron atoms in decomposed Fe and CO gas by chemical vapor condensation. According to the current invention, the synthesizing method includes vaporizing iron pentacarbonyl (Fe(CO)5) or iron acetate ((CH3CO2)2Fe) precursor to gas by use of a ceramic bubbler of a chemical vapor condensation device, decomposing the vaporized gas to Fe in a reactor of the device while being introduced with Ar gas, and condensing the decomposed Fe in a chamber of the device, thereby obtaining the Fe powders having sizes of tens of nm.