This study aimed to assess the level of nitrogen species in patients presented with acute myocardial infarction and to relate the levels of nitrogen species to the infarction site. A total number of 113 patients admitted to the intensive care unit at Diyala Teaching Hospital. The patients were presented within 6 hours of pain onset and diagnosed as acute myocardial infarction using electrocardiograph criteria and positive cardiac troponin test. The most common infarction site was anterior followed by inferior and lateral. Serum peroxynitrite level was significantly higher than healthy subjects by 100 folds and serum nitric oxide level is significantly reduced compared with healthy subjects by 50%. There were non significant differences in nitrogen species regarding the infarct sites. Associated risk factors e.g. hypertension, diabetes mellitus and smoking influenced the nitrogen species levels. It concludes that the significant alterations in nitrogen species not related to the site of acute infarction