Objective <p>The aim of this study was to compare the outcomes of skeletonized vs. pedicled internal mammary artery graft in coronary artery bypass grafting.</p> Methods <p>We retrospectively enrolled patients undergoing coronary artery bypass grafting in Nanjing First Hospital from 2020 to 2023. Patients were divided into two groups, skeletonized and pedicled internal mammary artery group. The outcomes were in-hospital mortality, deep sternal wound infection, blood flow and surgery duration. Kaplan-Meier estimation was used to depict the survival situation. Propensity score matching was used to minimize the effect of cofounders. Subgroup analysis was used to explore the outcomes in different population.</p> Results <p>A total of 2353 patients undergoing coronary artery bypass grafting were enrolled in this study. 1360 patients (57.8%) received skeletonized internal mammary artery and 993 patients (42.2%) received pedicled internal mammary artery. In primary and matched cohorts, the outcomes were not significantly different, except for blood flow. We found that blood flow of conduit and pulse index in skeletonized internal mammary artery were better that those in pedicle internal mammary artery in primary cohort(blood flow: 33vs31, <i>P</i> = 0.002 and pulse index: 1.9vs2.0, <i>P</i> &lt; 0.001) and matched cohort(blood flow: 32vs30, <i>P</i> = 0.002 and pulse index: 1.9vs2.1, <i>P</i> &lt; 0.001). The Kaplan-Merier curves showed that the survival rates were not significant difference between the two groups (<i>P</i> = 0.75). The results of subgroup analysis showed the similar results in different population.</p> Conclusion <p>Whether skeletonized or pedicled internal mammary artery conduits did not affect the in-hospital mortality, deep sternal wound infection, surgical duration and survival rate. Skeletonized internal mammary artery harvesting may offer physiological advantages in terms of graft flow in experienced hands, but further studies are needed to confirm its safety and clinical benefit.</p>