Abstarct: In the family of ultra-high temperature ceramics, compounds such as HfB2 have a unique combination of mechanical and physical properties of high heat shock resistance. Therefore, such materials are attractive options for high temperature structures (above 2000 °C). A common problem in the production of industrial parts from these compounds is the high sinter temperature. For this reason, other oxide or carbide compounds are used as sinter aids. In this research, an attempt has been made to use SiC as the second phase of booster and sinter assistance in the production of HfB2 components by SPS method. For further investigation, samples containing 20% by volume of SiC and different amounts of Nd2O3 (zero, 1, 2 and 3% by volume) were sintered at 1900 ℃ for 15 minutes. In this study, XRD tests, EDS elemental analysis, scanning electron microscopy (SEM) were used to study the microstructure, phases and elements in the samples. Archimedes test was used to evaluate the density of samples. Finally, the samples were exposed to oxidizing medium for 32 hours at 1400 °C and studied. The results showed the best density, stiffness, flexural strength for the sample containing 2% by volume of Nd2O3. The results of the study of oxidized samples also showed that the best resistance to oxidation was obtained for samples containing 2% by volume of Nd2O3. Also, the mechanism of resistance of this composite against oxidation is the formation of an oxide laxyer containing three phases of HfO2, HfSiO4 and SiO2.