<p>Petroleum graphite derived from petroleum residue is typically produced through the heat treatment of primary products such as coke or pitch. The mesophase structure formed at this stage governs crystal growth during graphitization and strongly influences the electrochemical behavior of graphite. However, the mesophase content and orientation do not necessarily evolve proportionally, making it difficult to isolate the intrinsic effect of domain orientation on graphite crystallinity and electrochemical performance. In this study, we report the effects of mesophase domain orientation on graphite crystallinity and the electrochemical performance of lithium-ion batteries while maintaining a constant mesophase content. The mesophase content is maintained at 94 wt% to isolate the effect of mesophase domain morphology. The synthesis conditions of the primary product were determined based on a first-order reaction-kinetic model and the Arrhenius relationship, enabling consistent mesophase content across different synthesis temperatures. The mesophase orientation parameter varies from 8.22 to 45.37 depending on the synthesis temperature, as confirmed by histogram analysis. Samples with controlled domain alignment retained their mesophase-derived structural characteristics even after graphitization. Notably, the mesophase orientation induced an inverse relationship between d₀₀₂ spacing and crystallinity, indicating that the structural characteristics of graphite after graphitization can be tuned by controlling the mesophase domain orientation. More importantly, the capacity retention at 5&#xa0;C, relative to that at 0.2&#xa0;C, increases from 66.9% to 88.6% by controlling the mesophase domain orientation. These results highlight that decoupling the mesophase orientation from mesophase content provides a practical strategy for tailoring the graphite structure and producing graphite materials favorable for high-rate charge–discharge applications.</p>