Background and Aim : The syndrome of angina or angina-like chest pain with a normal coronary angiogram, often referred to as syndrome X is an important clinical entity and has usually an excellent prognosis. Although the exact mechanism of this syndrome has not been clearly defined, the decreased coronary flow reserve(CFR) has been suggested as a most important etiology. The aim of this study was to elucidate the relation between CFR and Framingham Risk Score (FRS) in subjects with chest pain and normal coronary angiogram. Methods : 354 subjects (M:F= 186:168, mean age: 55짹11 years) with chest pain and a normal coronary arteriogram were enrolled. CFR using of transthoracic Doppler echocardiography (TTE) and adenosine or dipyridamole was measured within two weeks after coronary angiogram. We compared CFR with FRS . Results : 1.FRS was 12.6짹4.4 in subjects with CFR < 2.0. 2. FRS was 10.9짹5.5 in subjects with 2.0���CFR<3.0. 3. FRS was 9.75짹5.9 in subjects with CFR���3.0. 4.There was a significant difference in FRS between subjects with CFR < 2.0 and CFR���3.0.(p<0.001) 5. CFR had an inverted correlation with FRC (R=-.222, p<.001)(Fig). Conclusions : Our results suggest CFR is closely related to FRS and the impaired CFR can predict the high 10-year risk of coronary artery disease even in subjects with chest pain and normal coronary angiogram.