Objective: High baseline insulin and glucose levels and presence of accompanying dyslipidemia, which are considered in the pathogenesis of metabolic syndrome X, were also observed in patients with cardiac syndrome X, which is similar to metabolic syndrome X in many aspects. In this study we aimed to compare serum insulin, glucose and lipid levels in patients with coronary slow flow which is hypothesized as a subgroup of cardiac syndrome X with those of healthy subjects and determine the relation of corrected TIMI frame count (cTFC) with these levels. Methods: Forty-six patients with normal epicardial coronary arteries but determined as coronary slow flow in coronary angiography performed because of chest pain and 16 healthy subjects having normal coronary arteries but without coronary slow flow were included in this study. Maximal exercise stress test according to Bruce protocol was performed in all patients. Baseline serum insulin, glucose and lipid levels were measured from venous blood samples of patients in both groups. TIMI 'frame count' method was used for diagnosis of coronary slow flow. The relationship between the degree of coronary slow flow and serum insulin, glucose and lipid levels was investigated. Results: Exercise stress test results of both groups were considered as negative regarding ischemia. There were no differences between 2 groups in serum insulin, glucose and lipid levels. (p>0.05). No relationship were determined by correlations analysis between serum insulin, glucose and lipid levels and corrected TIMI frame count. Conclusion: Normal values of insulin, glucose and lipid levels in patients with coronary slow flow and lack of their relation with cTFC support the opinion that coronary slow flow is a separate from the cardiac syndrome X clinical entity.