A (Ti,W)C solid-solution powder was synthesized via high-energy milling and carbothermal reduction of a TiO(OH)(2), WO3, and graphite mixture. The phase evolution during the reduction of a system that contains TiO(OH)(2) is discussed and compared with TiO2 systems in terms of the X-ray diffractometry and thermogravimetric analysis results. It was found that the presence of water molecules in the hydrate system reduces the milling efficiency. However, there was no inhibitory effect on the reduction of the oxide mixtures or the synthesis of the (Ti,W)C.