Background— In the prospective, randomized Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, implantation of paclitaxel-eluting stents (PES) safely reduced the rates of ischemic target lesion revascularization (TLR) compared with bare metal stents (BMS) in patients with ST-segment–elevation myocardial infarction (STEMI) undergoing primary percutaneous intervention. Diabetes mellitus is a known predictor of adverse outcomes after percutaneous intervention in STEMI. We therefore sought to assess the impact of PES in diabetic patients with STEMI from the HORIZONS-AMI trial. Methods and Results— A total of 478 patients with diabetes and 2527 without diabetes were randomly assigned to receive PES versus BMS. The 12-month rates of ischemic TLR were significantly reduced by PES compared with BMS in both diabetic (11.2% versus 5.2%; hazard ratio [95% confidence interval]=0.45 [0.21 to 0.93]; P =0.03) and nondiabetic (6.8% versus 4.3%, hazard ratio [95% confidence interval]=0.63 [0.44 to 0.92]; P =0.02) patients. In patients with insulin-treated diabetes, PES compared with BMS reduced the 12-month TLR rate from 21.4% to 7.3% (hazard ratio [95% confidence interval]=0.35 [0.12 to 1.03]; P =0.046). Angiographic late loss and binary restenosis at 13 months were also significantly reduced in PES-treated diabetic patients. There were no significant differences between the BMS and PES groups in the 12-month rates of death, reinfarction, stroke, or stent thrombosis in either diabetic or nondiabetic patients. Conclusions— In the large-scale, prospective, randomized HORIZONS-AMI trial, implantation of PES compared with BMS in patients with STEMI and diabetes mellitus resulted in significant reductions in ischemia-driven TLR and angiographic restenosis at 1 year, with comparable safety outcomes, including stent thrombosis. These results suggest that PES can safely be used to reduce restenosis in high-risk diabetic patients presenting with STEMI. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00433966.