Data are limited about the relative efficacy of drug-eluting stents (DESs) versus bare-metal stents (BMSs) for the treatment of unprotected left main coronary artery (ULMCA) stenosis. The survey promoted by the Italian Society of Invasive Cardiology on ULMCA stenosis was an observational study involving 19 high-volume Italian centers of patients with ULMCA stenosis treated using percutaneous coronary intervention (PCI). From January 2002 to December 2006, of 1,453 patients identified with ULMCA stenosis treated with PCI, 1,111 were treated with DESs and 342 were treated with BMSs. During a 2-year follow-up, risk-adjusted survival free from cardiac death was significantly higher in patients treated with DESs than in those treated with BMSs. The propensity-adjusted hazard ratio for risk of 2-year cardiac mortality after DES versus BMS implantation was 0.49 (95% confidence interval 0.32 to 0.77). The benefit of DESs in reducing cardiac mortality was obtained in the period from 3 to 6 months and maintained up to 2 years. In conclusion, for patients with ULMCA stenosis undergoing PCI, DES implantation was associated with higher adjusted rates of 2-year survival free from cardiac death. The benefit of DESs in reducing cardiac mortality was obtained in the period in which clinical manifestations of restenosis usually peak.