Background: The long saphenous vein is routinely used for coronary bypass graft (CABG) surgery, and two primary techniques are commonly utilized: endoscopic vessel harvesting (EVH) and open vessel harvesting (OVH). The aim of this study was to compare the clinical outcomes of the EVH and OVH techniques used for CABG within the confines of a tertiary hospital. Methods: The clinical data of all patients subjected to either EVH or OVH for CABG surgery between 2014 and 2018 were retrospectively analyzed. Statistical analysis was performed to discern variations in the rates of postoperative complications between EVH and OVH. Results: A cohort of 1884 individuals were included in this study, 75.3% of whom underwent EVH. Notably, the incidence of postoperative leg wound complications was significantly different between the patients who underwent OVH and the patients who underwent EVH, with incidence rates of 18.6% and 32%, respectively (p < 0.001). Leg wound complications (p < 0.001; OR 1.946; 95% CI 1.528-2.477) and leg wound infections (p = 0.050, OR 1.517, 95% CI 0.999-2.303) were significantly associated with OVH. Moreover, leg wound hematoma (p = 0.039, OR = 0.402, 95% CI = 0.169-0.957) and EVH were strongly associated. Conclusions: The large sample of patients and the inclusion of a range of Asian ethnic groups provided notable insights into postoperative complications related to different modalities. EVH was associated with a lower incidence of postoperative leg wound complications, which suggests that EVH is a better modality for those undergoing CABG surgery.