Objective To investigate the renal function of the patients with acute myocardial infarction (AMI) and its effect on patients' outcome.Methods The renal function of 680 patients with AMI,received the conventional therapies, such as thrmbolysis, antiplatelet and antianginal therapies were investigated. According to it, 228 patients with renal dysfunction[GFR ＜90ml · min-1 · ( 1.73m2 ) -1]were divided into observation group,while the others[GFR≥90ml · min-1 · (1.73m2) -1]were divided into control group. To analyse their clinical characteristics、the inhospital mortality、one year mortality and the heart ocurrence rate in one year. Results Compared with the patients in the control group,the patients in the observation group were older、more likely to be women、and more likely to have hypertension、diabetes mellitus、coronary heart disease. The inhospital and one year mortality were higher ( 17. 8％ vs 9.74％ ,P ＜0. 01 ;25.00％ vs 14. 44％ ,P ＜0. 01 ) and the heart ocurrence rate was higher(57. 14％ vs38. 96％ ,P ＜ 0. 01 ) in one year in the observation group than that in the control group. ConclosionThe AMI patients with renal dysfunction were more likely to have concomitant diseases, worse ill condition and outcome. Renal dysfunction was an independent risk factor for the outcome in the patients with AMI.