Tetragonal solid solutions based on the TiO₂–CeO₂–ZrO₂ system stable up to 1,350°C were obtained. A method of pH titration of the initial salt mixture was used to study the competitive hydrolysis and precipitation processes in a three-component system. The microstructure and specific surface area of the precursors after synthesis were studied. Adetailed study of precursor phase formation in the range from 600 to 1,350°C was performed using STA, XRD, and laser sedimentography methods. It was shown that for all the studied compositions, an increase in temperature to 1,100°C results in a competitive phase formation accompanied by de-agglomeration in the system up to 1,000°C.