Background Acute kidney injury (AKI) is common in patients with acute myocardial infarction. AKI in this setting is associated with short- and long-term adverse events. The aim of this study was to develop a simple score to predict AKI in patients presenting with acute myocardial infarction based on data available at time of admission. Methods This was a retrospective analysis of data collected as part of the Acute Coronary Treatment and Intervention Outcomes Network (ACTION) registry at a tertiary care center between 1/1/2011 and 12/31/2013. Data were collected prospectively for all patients who presented within 24 h of the onset of myocardial infarction. AKI was defined as an increase in creatinine from admission level to peak level of >= 0.3 mg/dl or by >= 50 %. Patients with history of end-stage renal disease requiring renal replacement therapy were excluded. Results Of 1107 patients included in the study, 147 (13.3 %) developed AKI. The following factors were independently associated with increased risk for AKI: cardiac arrest, decompensated heart failure on presentation, diabetes mellitus, hypertension, anemia, impaired renal function on presentation, and tachycardia on presentation. These factors were combined to form a new predictive tool. The new score showed excellent discrimination for AKI: the area under the receiver operating characteristic curve (AUROC) was 0.76 (95 % confidence interval 0.72-0.80). Conclusion A simple score using clinical and laboratory data available on admission can predict the risk of AKI in patients presenting with acute myocardial infarction.