Background: Korea Acute Myocardial Infarction Registry (KAMIR) study has been supported by the Korean Circulation Society in the memorandum of the 50th Anniversary of the Korean Circulation Society since Nov 2005. Methods: On-line registry of acute myocardial infarction at the web site of www.kamir.or.kr has been performed in 40 primary percutaneous coronary intervention (PCI) centers in Korea. Two thousand six hundred seventy six patients out of 3,239 patients (2,286 male, 63.7짹12.7 years) who underwent primary percutaneous coronary intervention (PCI) between Nov 2005 and Apr 2006 were eligible for the analysis of the low-density lipoprotein-cholesterol (LDL-C) and the success rate of primary PCI enrolled in KAMIR. Results: The incidence of ST elevation myocardial infarction was more common in than non-ST elevation myocardial infarction [1,911 patients (60.3 %) vs. 1255 patients (39.6 %), p=0.043]. Killip class was 2,153 (73.1 %) in class I, 447 (15.1 %) in II, 224 (7.6 %) in III and 118 (4.0 %) in IV. Mean level or LDL-C was 118.3짹43.1 mg/dL. The mean level of LDL-C was increased according to the level of body mass (LDL-C<70 mg/dL, BMI 22.7짹3.4 kg/m2; 70 mg/dL< LDL-C<100 mg/dL, BMI 22.7짹3.4 kg/m2; 100 mg/dL< LDL-C<130 mg/dL, BMI 23.9짹3.0 kg/m2; 130 mg/dL< LDL-C<160 mg/dL, BMI 24.3짹3.2 kg/m2; 160 mg/dL< LDL-C<100, BMI 24.5짹3.2 kg/m2, p<0.0001). The primary success rate of primary PCI was correlated with the level of LDL-C (Table) Conclusion: Increased level of LDL-C is associated with high success rate of primary PCI in Korean AMI patients.