Objectives: Peak troponin Ic (cTnI) level could be influenced by renal function. We evaluated the effect of moderate to severe renal failure on peak cTnI level during acute myocardial infarction (AMI). Methods: One hundred and twenty-five consecutive patients admitted to the coronary care unit of a university hospital in France for primary angioplasty during AMI were retrospectively studied. Results: The correlations between peak cTnI level, peak creatine phosphokinase (CK) level, peak cTnI/peak CK ratio and creatinine clearance (CrCl) were assessed. The peak cTnI/peak CK ratio was considered in order to standardize the peak cTnI level with the extent of myocardial necrosis. There was no significant correlation between CrCl and peak CK (r = 0.01, p = 0.95), peak cTnI (r = –0.08, p = 0.38) or the peak cTnI/peak CK ratio (r = –0.14, p = 0.13). There was a trend towards higher peak cTnI in patients with moderate to severe renal failure. The peak cTnI/peak CK ratio did not significantly differ among patients according to CrCl stratification, whereas the ratio of log-transformed values was significantly higher in patients with moderate to severe renal failure. Conclusion: In patients with AMI, the peak cTnI level seemed to be influenced by renal function.