Introduction:Hyperhomocysteinemiais a disease involving abnormal homocysteine metabolism and is characterized by increased level of total homocysteine concentration (normal 5-15?mol/L). Many factors like dietary folate, cynocobalamine deficiency or thyroid disorders are the most common causes for increased homocysteine level. Thus this present study was planned to delineate the usefulness of levothyroxin to evaluate changes in homocysteine level in hypothyroid patients. Material And Method: The present study was conducted on 75 patients of hypothyroidism of either sex in Department of Biochemistry, J.L.N. Medical College & Hospital, Ajmer. Serum homocysteine level was measured by ELISA while thyroid function tests were evaluated by RIA method. Result And Discussion: Before treatment serum homocysteine level was higher in hypothyroid patients (17.10?3.09?mol/L) as compared to normal subjects (8.15?n0.345?mol/l). During treatment a significant decrease was observed in hypothyroid patients (10.81?1.96?mol/L) Conclusion: It is concluded thatsupplementation of thyroxin in hypothyroid patients can cause significant decrease in level of homocysteine which can further decrease risk of coronary artery disorders in these patients .