The oxidation of diesel fuel was studied using the vibrofluidized and fluidized beds of disperse river sand in the presence of iron-containing microspheres isolated from the fly ash of coal boiler stations: ferrospheres and cenospheres activated with iron oxide. The results were compared with the available data on the oxidation of diesel fuel using the microspheres of commercial catalysts for complete oxidation of organic compounds. In the presence of ferrospheres and cenospheres with deposited iron oxide at 500–600°C, deeper oxidation of diesel fuel was observed than in the vibrofluidized bed of an inert material (river sand). The most complete oxidation (84.3%) was observed with ferrospheres at 700°C. The ferrospheres used in the oxidation of diesel fuel in the fluidized bed of the inert material showed lower activity under these conditions than the commercial catalysts based on СuСr 2 О 4 /А1 2 О 3 and disperse Fe 2 O 3 . Nevertheless, higher oxidation rate, 97.8%, can be achieved in the presence of ferrospheres by arranging flare combustion of diesel fuel above the bed. In this case, the flame length decreases by half compared with that above the bed of the inert material. This, as well as the decreased CO content and unburnt carbon in combustion products, indicate the catalytic activity of ferrospheres fed to the flame.