Thermolysis of ferrocenium tungstophosphate [(C5H5)2Fe]3[PW12O40]∙H2O and tungstophosphatoferrates with the general formula of Cat4[PW11O39Fe(H2O)]∙ m H2O, where Cat = (NH4)+, Rb+, Cs+, (CH3)4N+, with the Keggin anion structure were studied using differential scanning calorimetry, infrared spectroscopy, X-ray phase analysis, and electron microscopy. The crystalline products of their thermal decomposition - phases with the structure of pyrochlore and tungsten bronzes - were identified. The synthesized compounds are catalysts for the oxidation reactions of organic compounds and the production of carbon nanomaterials.