Abstract The aim of the present research work was to investigate the effect on the properties such as density, surface roughness, microhardness, fracture toughness and microstructure added with MgO and ZrO 2 in an alumina matrix. The magnesia-zirconia toughened alumina spark plasma sintered nanocomposite samples were developed successfully and found the suppressing grain growth and crack free microstructure. No damage was found due to thermal shock up to 1350 °C. The amount of ZrO 2 was added with 5 vol%, 10 vol% and 15 vol%, while MgO added with 0.5 vol%, 1 vol% and 2 vol% in an aluminamatrix. Each composition was weighed and mixed together. After that, the powders were pressed under the rapid heating at the sintering temperature of 1250 °C, 1300 °C and 1350 °C and for 5 min holding time under pressure of 60 MPa simultaneously. The optimum properties were found with the compositions of 10 vol% of ZrO 2 , 1 vol% of MgO in the Al 2 O 3 matrix. It showed highest relative density (99.68%), minimum surface roughness (1.123 μm), highest microhardness (19.46 GPa) and minimum average grain size (0.595 μm). The highest fracture toughness was found to be 6.7 MPa.m1/2 the added with 15 vol% of ZrO 2 ,1 vol% of MgO in the Al 2 O 3 matrix for the holding time 5 min and a sintering temperature of 1300 °C. The X-ray diffraction analyses indicate the presence of major phases were ZrO 2 , α-Al 2 O 3 , MgO, magnesia phase with minor peaks of the secondary phase MgAl 2 O 4. This was found due to chemical reactions between the composite constituents present in the matrix during the sintering. Uniform microstructure was observed using a field emission scanning electron microscope and obtained the sub-micron level of grain size without any significant increases of grain size. The developed compositehas high hardness and toughness to make it more suitable for applications such as ballistic armor and thermal barrier coating. Highlights • Investigations on the effect on the properties added with ZrO 2 and MgO in the alumina matrix using the SPS process. • Relative density, minimum surface roughness, microhardness, and fracture toughness were studied. • Uniformly distributed grain particles and densification of microstructure were found. • The indexed of the major peaks were found to be ZrO2, α-Al2O3, MgO and one minor secondary phase was found to be MgAl2O4. • The possibility of the secondary phase of MgAl2O4 of SPS sintered sample of MgO-ZTA due to each sample contained Mg element. [ABSTRACT FROM AUTHOR]