An investigation has been carried out into the effect of TiO2 addition on the sintering, phase stability and room temperature mechanical properties of cubic zirconia (c-ZrO2). C-ZrO2 specimens containing TiO2 addition up to 10 wt% were produced by colloidal processing and pressureless sintering. The sintered density of the specimens decreased with increasing TiO2 content up to I wt% and further increase in TiO2 content led to a increase in the sintered density. XRD results showed that when the TiO2 amount was less than 5 wt%, the specimens were entirely single cubic phase; further addition of TiO2 (5 wt% or more) destabilized cubic zirconia phase and caused the formation of tetragonal phase. The amount of tetragonal phase increased with increasing TiO2 content in c-ZrO2 matrix. The room temperature mechanical properties of flexural strength and fracture toughness both increased with increasing TiO2 content. (c) 2006 Elsevier Ltd. All rights reserved.