This research focuses on the production of high-temperature ceramic matrix composites based on silicon carbide and investigates the possibility of simultaneously using TiB2 additives and graphene quantum dots (GQDs) to enhance mechanical properties. The aim of this research is to produce silicon carbide matrix composites with high mechanical properties such as hardness, fracture toughness and Young's modulus higher than pure silicon carbide. The samples were prepared with different amounts of additives and a proportional amount of silicon carbide matrix powder and were sintered at 2150°C. Subsequently, the optimal conditions for the production of these composites were determined by microstructural, phase, fracture, and mechanical properties studies. According to the results, by increasing TiB2 to about 20% by weight, the hardness of the composite increases and reaches its maximum value of 27.15 GPa. The highest fracture toughness, Young's modulus, and hardness were obtained for the sample containing 20 wt% TiB2 and 0.3 wt% GQD.