To review the current evidence for coronary revascularization in patients with diabetes mellitus (DM) in the setting of an acute coronary syndrome (ACS). In patients with DM and stable multivessel ischemic heart disease, coronary artery bypass graft surgery (CABG) has been observed to be superior to percutaneous coronary intervention (PCI) in long-term follow-up, leading to lower rates of all-cause mortality, myocardial infarction, and repeat revascularization. In the ACS setting, PCI remains the most frequently performed procedure. In patients with an ST-segment-elevation myocardial infarction (STEMI), primary PCI should be the revascularization method of choice, whenever feasible. Controversy still exists regarding when and how to deal with possible residual lesions. In the non-ST-segment-elevation (NSTE) ACS setting, although there are no data from randomized controlled trials (RCTs), recent observational data and sub-analyses of randomized studies have suggested that CABG may be the preferred approach for patients with DM and multivessel coronary disease. There is a paucity of RCTs evaluating revascularization strategies (PCI and CABG) in patients with DM and ACS. CABG may be a viable strategy, leading to improved outcomes, especially following NSTE-ACS.