Subclinical hypothyroidism (SCH) is evaluated as an increased serum thyroid-stimulating hormone (TSH) above the given upper limit of the reference range, with free thyroxine (free T) and free triiodothyronine (free T) within the reference range. Thyroid hormones play major role in the growth, development and physiology of the renal system. The study was performed to evaluate renal functions in SCH cases. The study was conducted at Smt SMS Multispecialty hospital. 50 SCH and 50 overt hypothyroidism (OHT) cases, 100 euthyroid patients (ET) were enrolled in the study. Thyroid function test, serum creatinine and eGFR were measured in all the three groups. The result shows that there was a definitive trend of increased serum creatinine from euthyroid group to SCH group and finally to OHT group and definitive trend of decreased eGFR from euthyroid group to SCH group and finally to OHT group. Among the three groups, there are higher percentage of patients having high serum creatinine and low eGFR belongs to SCH and OHT group in comparison to ET group. Our result showed a significant positive correlation of TSH with serum creatinine in cases of SCH and OHT and significant negative correlation of TSH with eGFR in cases of SCH and OHT. Finding of our study suggests that renal function and thyroid function are interrelated with each other in SCH cases. SCH patients should be monitored for renal parameters regularly to prevent long term complications. Early diagnosis and early treatment of the disease and can increase the quality of life.