This study investigates the influence of titanium carbide (TiC) content on the microstructure and mechanical properties of molybdenum (Mo)-based composites, aiming to provide a scientific basis for the development of high-performance, heat-resistant molybdenum materials for aerospace engines. TiC/Mo composites containing 10%, 20%, and 30% TiC were prepared using spark plasma sintering (SPS) technology. The results indicate that the strengthening mechanisms of TiC/Mo composites are primarily attributed to intragranular particle strengthening and grain boundary strengthening. At elevated temperatures, TiC diffuses into the Mo matrix, forming a transition zone of measurable width at the interface of the two phases. XRD analysis confirms that this transition zone comprises (Ti, Mo)C. The crystal lattices of the TiC and Mo phases exhibit strong bonding, which is further corroborated by atomic-scale observations. Tensile and hardness tests reveal that TiC/Mo composites with 10 wt% and 20 wt% TiC demonstrate superior mechanical properties. The fracture behavior of these composites is primarily governed by the propagation of intergranular microcracks, which is influenced by the competition between intergranular and intragranular crack development. This study provides critical insights into the coupling effects of intergranular and intragranular TiC particles on the mechanical performance of TiC/Mo composites.