Aim To research the clinical significance of red blood cell distribution width(RDW) and mean platelet volume(MPV) on the formation of coronary collateral circulation(CCC) in patients with non-ST segment elevation myocardial infarction. Methods 166 patients with non-ST segment elevation myocardial infarction from Department of Cardiology of Nanyang Central Hospital and Henan Provincial People's Hospital were divided into impired group(n=98) and CCC good group(n=68) according to retrop classification method for grading CCC. RDW and MPV value were measured by automatic blood cell analyzer. Results RDW values were significantly higher in patients with impaired CCC than that in those with good CCC(18.20%±1.83% vs 13.17%±0.84%, P<0.05),and MPV values were observably lower in patients with impaired CCC than that in those with good CCC(8.16±1.22 fl vs 11.31±1.34 fl, P<0.05). In multivariate logistic regression analysis, high RDW, low MPV, high creatine kinase isoenzyme-MB(CK-MB), absence of preinfarction angina were closely related with impaired CCC. Conclusion In non-ST segment myocardial infarction, high RDW, low MPV, high CK-MB, absence of preinfarction angina were found to be independent predictors of impaired CCC.