BACKGROUND: Ischemia Modified Albumin (IMA) is an ischemia/reperfusion injury marker which has been considered to be formed under oxidative stress conditions. Endothelial L-Arginine/NO pathway dysfunction can lead to oxidative stress which has deleterious effects seen on the vascular wall causing ischemia. AIM: 1) The study was conducted to estimate the levels of IMA and NO in hyperthyroidism patients. 2) To evaluate the relationship between IMA and NO levels in hyperthyroidism. MATERIALS AND METHODS: A cross sectional study was done with 30 newly diagnosed hyperthyroid patients as cases and 30 age and sex matched healthy controls. Serum levels of IMA and NO were estimated by colorimetric methods and thyroid profile was done by ELIFA methodology. STATISTICAL ANALYSIS: Data were analyzed using SPSS. Values were expressed as Mean±SD. RESULTS: Nitric Oxide levels were significantly decreased in hyperthyroid patients (7.08±1.57µmol/L) as compared to healthy controls (39.76±4.98µmol/L) (p=0.001). Ischemia Modified Albumin levels were found to be significantly increased in hyperthyroid patients (0.73±0.10 ODU) when compared to healthy controls (0.28±0.01 ODU) (p=0.001). CONCLUSION: In our study there was increase in IMA levels with decreased NO levels which could be due to the consequence of oxidative stress and ischemia which is present in hyperthyroidism.