Abstract Y‐TZP (YZ) and Al 2 O 3 ‐doped Y‐TZP (AYZ) bioceramics with addition of different contents of a refractory bioglass were fabricated. The influence of the glass addition and sintering temperature on the densification behavior, microstructure, and mechanical properties of YZ and AYZ was studied. The developed ceramics contained small amounts of ZrSiO 4 and Ca 2 P 2 O 7 phases within the ZrO 2 matrix. The incorporation of glass to YZ promoted the ZrO 2 phase partitioning and enhanced the ZrO 2 grain growth at all the sintering temperatures, whereas the glass addition in AYZ prevented the Y 2 O 3 redistribution between ZrO 2 grains and limited the ZrO 2 grain growth at 1300–1400°C. The hardness of the samples with glass was not significantly altered by using either YZ or AYZ. A slight increase in the fracture toughness with increasing glass content was found for YZ, while the fractured toughness of AYZ decreased by the glass addition. The more pronounced ZrO 2 phase partitioning of YZ with glass decreased the flexural strength, whereas AYZ maintained almost unaltered its flexural strength at a high level by the glass incorporation.