Objective To investigate the effects of different graft geometries on the hemodynamic characteristics of coronary artery bypass grafting (CABG) using computational fluid dynamics (CFD). The aim is to optimize postoperative blood flow distribution, improve long-term surgical outcomes, and provide guidance for selecting the optimal surgical plan. Methods Based on CT data from real patients, three-dimensional models of coronary arteries were reconstructed using SimVascular software. Four grafting strategies were designed: single bypass, Y-shaped bypass, sequential bypass, and V-shaped bypass. CFD simulations were conducted to analyze and compare coronary artery flow, graft flow, wall shear stress (WSS), oscillatory shear index (OSI), and relative residence time (RRT) for each strategy. Results All four bypass strategies effectively restored blood flow distribution; however, the sequential bypass showed the best performance in terms of WSS on the graft vessel wall, with its WSS values remaining within the ideal range. In contrast, some regions of the Y-shaped and V-shaped bypasses showed risks of insufficient WSS. Furthermore, OSI and RRT analyses indicated that the sequential bypass and single bypass demonstrated advantages in these metrics, exhibiting a more stable blood flow environment. Conclusion The impact of different grafting strategies on coronary hemodynamics varies. This study demonstrates that coronary grafts with different geometries have distinct hemodynamic effects, especially in key indicators such as WSS, OSI, and RRT. The sequential bypass has potential for better long-term outcomes, effectively reducing the risk of post-operative graft failure and atherosclerosis. The choice of surgical approach should consider the patient's specific anatomical and pathological characteristics to optimize post-operative results. The findings of this study provide theoretical guidance for the design and optimization of treatment plans for left anterior descending artery (LAD) bypass surgery.