Directional cracking in Ti,C:sapphire crystals grown along 1120 by Vertical Bridgman method often occurs in the cutting and processing process. In this work, we discuss the characteristic and mechanism of directional cracking of Ti,C:sapphire, and find that directional cracking originates from (1100) lattice plane and spreads along 0001 orientation. Through the Crystalmaker Simulation software, we find that atomic arrangement on (1100) lattice plane is the most sparse and adjacent atomic spacing is the largest along vertical 0001 direction, so in the system (1100) 0001 of lattice has a minimum cracking strength. Irregular carbon inclusions in the cracked Ti,C:sapphire are observed with optical microscopy, scanning electron microscopy (SEM), and X-ray diffractometry. These inclusions cause great internal stress in the cooling process due to thermal expansion mismatch and cracking originating from and spreading in the weak system (1100) 0001 of lattice. As a consequence, macroscopic directional cracking is observed in the Ti,C:sapphire. The study has important theoretical and practical significance for growing high-quality Ti,C:sapphire crystal.