Abstract: AIM:To evaluate the association between estimated glomerular filtration rate (eGFR) and coronary slow flow (CSF) in patients with normal to mildly impaired renal function. METHODS: Fifty patients with angiographically proven CSF and 51 controls were enrolled in this study. Modification of diet in renal disease equation was used to assess the eGFR. RESULTS: eGFR rate was mildly decreased and serum uric acid levels in the CSF group were higher. Patients with mildly impaired renal function had higher thrombolysis in myocardial infarction frame counts in three major coronary arteries. Logistic regression analysis showed that uric acid (OR 1.007, 95% CI 1.0-1.013, P=0.038), eGFR (OR 0.968, 95% CI 0.938-0.999, P=0.045) and smoking (OR 3.513, 95% CI 1.135-10.869, P=0.029) were independent risk factors for CSF. CONCLUSION: eGFR is significantly correlated with CSF in patients with normal to mildly impaired renal function.