The observational study was a retro-selective, unicenter, nonrandomized study to evaluate the clinical safety and efficacy of the stainless steel and cobalt-chromium alloy stent. Use of the cobalt-chromium alloy in place of stainless steel offers enhanced visibility and radial strength with thinner structural elements. The study enrolled 128 patients with symptomatic ischemic heart disease attributable to de novo or restenotic nonstented native lesions of a single vessel amenable to percutaneous stenting. The primary composite end point was the incidence of major adverse cardiac events (death, myocardial infarction, emergency bypass surgery, or target lesion revascularization) 365 days after PCI. The mean age of patient was 56.17 ± 10.43 years, with 50.81% and 47.36% of unstable angina patient. No difference in most clinical angiographic characteristic between two groups. At 1 month follow up there was no significant difference between two groups (p = 0.96). The individual clinical component showed no difference in occurrence of death (p = 0.29), MI (p = 0.29) and TLR (p = 0.96) at end of 6 month. At 1 year MACE occurred 8.1% in cobalt chromium group and 14.0% in stainless steel stent (p = 0.31). Rate of TLR was 0 % in cobalt chromium group and 3.5% in stainless steel stent (p = 0.14). The incidence of restenosis was 3.27 % in cobalt chromium group and 7.01% in stainless steel stent (p = 0.35).