The ceramic powders of the system ZrO2−Y2O3 are used in solids electrolytes fabrication for fuel cells because of its high ionic conductivity. As much the morphology as the particle size of the ceramic powders are important characteristics for the determination of the electric properties of the device; this is the reason to study the particles mechanisms formations during the development of the synthesis method. It is important the control of the involved parameters during the process to obtain ceramic powders with micro-structural and physical properties predetermined. ZrO2 doped with Y2O3 was synthesized using Controlled Precipitation Method (CPM), and Polymeric Precursor Method (Pechini). The obtained products were nano-metric ceramic powders of ZrO2 in cubic phase. The powders were characterized using X-ray diffraction (XRD), Fourier Transformed Infrared Spectroscope (FTIR) and Transmission Electronic Microscopy (TEM) Also, with base in the experimental results, it is proposed a mechanism for the particles formation.