ABSTRACTZrO2 composite ceramics containing 10~30 mol% Al2O3 and 1.5 mol% Y2O3, i.e., 90~70 mol% ZrO2(1.5 mol% Y2O3)-10~30 mol% Al2O3 ceramics, have been fabricated by sintering cubic ZrO2 solid solution (ss) nano-powders prepared via the neutralization co-precipitation method. The sintering was performed using a pulsed electric-current pressure sintering (PECPS) at 1598 K for 10 min under 50~60 MPa in Ar. Dense tetragonal-ZrO2 (ss) ceramics containing α-Al2O3 were composed of 277-130 nm grains. FE-SEM observation revealed that their microstructures, that is the grain sizes of both t-ZrO2 (ss) and α-Al2O3, and the distribution of α-Al2O3 particles, were much influenced by the content of α-Al2O3. The best mechanical properties of extreme high bending strength (σb ≥ 1 GPa) and high fracture toughness (KIC ≥ 15 MPa • m1/2) simultaneously were obtained at the composition of 25 mol% Al2O3 with a high relative density 99.9 %, as the same composition reported for the HIP sintered ZrO2(2~3 mol% Y2O3)-Al2O3 composite ceramics.