Abstract: Elliptical microvoid flaws with different sizes were defined and introduced into the calibrated discrete-element model of SiC ceramics. Effects of inclination angle, aspect ratio and area of the microvoid on the compression properties of SiC ceramics were studied by uniaxial compression simulation. The results show that the presence of microvoids reduced the compressive strength and elastic modulus of the sample and improved the Poisson's ratio. With a relatively small inclination angle, the larger the aspect ratio of the microvoid, the smaller the compressive strength and elastic modulus of the sample, and the higher the Poisson's ratio. With increasing inclination angle, the effect of the aspect ratio on the compressive strength, elastic modulus and Poisson's ratio gradually decreased. When the inclination angle increased above 60°, the compressive strength, elastic modulus and Poisson's ratio were close to those of the non-defective samples. With decreasing microvoid area, the effect of the aspect ratio and inclination angle on the compressive strength of the sample gradually decreased. When the aspect ratio of the microvoid was 1 or the inclination angle was 90°, increasing the void area had little effect on the compressive strength.