Abstract: The association between serum Homocysteine (Hcy) and myocarditis in calves with Foot and Mouth Disease (FMD) are not well defined. To investigate the relationship between serum Hcy concentrations and myocarditis in healthy calves and calves with FMD. A total of 9 healthy calves (control) and 15 calves with FMD. In the study, all animals underwent a comprehensive clinical and laboratuar findings study to document cardiac health or presence of FMD. Blood samples were collected via jugular venipuncture. Serum Hcy, Nitric Oxide (NO), cardiac Troponin I (cTnI) concentrations, serum levels of activity Creatine Kinase (CK), Lactac Dehydrogenase (LDH) and cardiac origin Creatine Kinase (CK-MB) were measured. Serum Hcy, NO, cTnI, CK, CK-MB and LDH values in calves with FMD significantly higher compared to control (p<0.01, p<0.001, p<0.01, p<0.001, p<0.001 and p<0.05, respectively). The results suggest that determination of serum Hcy concentrations in calves with clinical signs compatible with FMD might prove useful as a guide to quantify cardiac remodeling associated with heart damage.