Introduction: The retromolar area is a commonly utilized donor site for autogenous bone grafts in oral and maxillofacial surgery. However, the close proximity of the mandibular canal (MC) poses a risk of neurovascular injury. A thorough understanding of anatomical variations in the position of the MC with respect to sex and age is essential to ensure safe surgical interventions. This study aimed to assess the position of the MC using cone-beam computed tomography (CBCT) and to identify potential safe zones for bone harvesting in the retromolar region. Materials and Methods: A total of 100 CBCT scans were analyzed. Key measurements included the vertical distance from the cementoenamel junction to the MC, canal depth at the transition zone between the mandibular ramus and body, and the buccal bone thickness overlying the MC. The data were categorized by sex and age group and statistically compared. Results: Male subjects demonstrated significantly greater buccal bone thickness (mean difference: 1.5 mm) and canal depth compared to females. Younger individuals (Group 1) presented with increased bone thickness and greater canal depth at the level of the first molar. At the second molar level, canal depth was significantly higher in males. Conclusion: The transition zone between the mandibular ramus and body emerges as the most favorable area for safe retromolar bone harvesting, owing to its increased canal depth and lingual positioning of the MC. However, no absolute safe zone was identified, underscoring the importance of patient-specific radiological assessment prior to grafting procedures.