The aim of this research is to investigate the combined effects of CeO2 additions and hot-isostatic pressing sintering (HIPping) technique on the densification of ZTA ceramics. Addition of CeO2 to ZTA ceramics leads to formation of a secondary phase (CeAl11O18) which played a vital role in affecting the density and porosity. Microstructure investigations showed that HIPping had a significant role in the removal of pores. The sample with 5 wt.% of CeO2 addition showed the optimum value. The highest bulk density is 4.46 g/cm3 and the lowest percentage of porosity is 0.35%.