Background: The two main first generation drug-eluting stents (DES); Sirolimus- (SES; Cypher) and Paclitaxel (PES; Taxus) eluting stent is effective in reducing intimal hyperplasia but recently safety issues related to profound delayed healing and associated stent thrombosis was suggested. We compared the mid-term safety and efficacy of those two first generation DESs implanted in unprotected left main (LM) angioplasty. Methods: All patients (pts) with unprotected LM lesion were electively treated either with SES or PES. LM bifurcation lesions were treated by kissing stenting, crushing technique or stent crossover (Stent/Balloon). Clinical and angiographic outcomes at 6 months were investigated. Results: Out of total 69 pts who underwent standard percutaneous coronary intervention (PCI) on unprotected LM lesion, 36 pts (36/69, 52.2%) were exclusively treated with SES and 21 pts (21/69, 30.4%) with PES. There was a trend toward more GP IIbIIIa blockers usage for fear of acute stent thrombosis at the index procedure, esp in the SES group. At 6 months, although binary restenosis tend to be higher in the PES group but clinical outcomes showed no significant differences between the groups (Table). Conclusion: SES implantation was more associated with use of GP IIbIIIa blockers and less angiographic binary restenosis compared with the PES. However, mid-term clinical outcomes were favorable and similar between the SES and PESs.