Background : Thyroid hormone plays a critical role in cardiomyocyte maturation and stress-related cellular responses like AMI. The inhibition of thyroid hormone receptor alfa (TRα) causes down regulation of this hormone in post-ischemic myocardium. On the other hand, ferritin, an inflammatory marker; and testosterone, a hormone which alters lipid profile, also play significant roles in pathogenesis of AMI. The objective of our study was to compare thyroid profile (total T3, T4 and TSH), ferritin, Vitamin B-12, folic acid and testosterone in newly diagnosed male cases of AMI with age-matched controls. We also contrasted these biochemical parameters between AMI subgroups with very low and low left ventricular ejection fraction (LVEF). Methodology :A cross-sectional study was conducted from September, 2012 to February, 2013 at a tertiary care hospital of north India. Newly diagnosed male AMI patients with positive clinical and ECG findings, and CPK MB > 25 U/L (spcetrophotometric method) and Troponin-I ultra > 2ng/ml (chemiimmunofluroscence method) were enrolled as cases (n=43). Cases were further sub-classified into those with very low LVEF (<35%, Group 1) and low LVEF (35-50%, Group 2). Serum was pooled at 12-24 hr of onset of symptoms and preserved at-20°C until analyzed. Serum TSH was measured with immunoradiometric assay; serum T3 and T4 were measured with radioimmuno assay. Serum ferritin, Vitamin B-12, folic acid and testosterone were also estimated (chemiimmunofluroscence method) in all cases. 40 age and sex matched controls were similarly examined. Result :AMI patients reported significantly lower T3, higher ferritin and lower testosterone level in comparison to control group. On the other hand, cases with lower LVEF (<35%) showed significantly lower value of CPK MB, T3, ferritin and testosterone. Conclusion :Our study found down regulation of T3 and testosterone levels, with raised higher ferritin levels in patients suffering from an acute attack of AMI.