In the present work, the synthesis of the hydrated citrate of Pr by amorphous citrate method under the same conditions used for the preparation of PrBa2Cu4O8 system, is reported. The thermal decomposition of the complex was studied in air, nitrogen and oxygen, in order to investigate and identify the final oxides and the intermediates obtained during decomposition. A special attention was paid to the thermal decomposition of the Pr-carbonate octahydrate used in the synthesis as starting material. The experiments were performed by thermogravimetry. differential thermal analysis, X-ray diffraction and infrared spectroscopy.