Thyroid hormone abnormalities are the commonest endocrine disorder in India and also the commonest preventable cause of mental retardation. In the absence of neonatal screening, thyroid disorders remain largely unrecognized in Indian children. To determine the prevalence, clinical profile, aetiology and associated co-morbidities of thyroid dysfunction in children. A prospective, hospital based, observational study was conducted at a tertiary care hospital in Western India. Children below 12 years of age visiting the Pediatric out-patient department (OPD) and in-patient department (IPD) were included if they had clinical suspicion of thyroid dysfunction. Demographic data and clinical features of the recruited children were noted along with family history of thyroid disorders and use of iodized salt. Thyroid profile consisting of Tri-iodothyronin (T3), Thyroxin (T4) and Thyroid stimulating hormone (TSH) levels were tested in all. Investigations were also carried out to look for the cause and complications of hypothyroidism. These children were also followed up with appropriate therapy to look for response of therapy and complications to the same. Sixty five children were found to have thyroid function abnormalities, 61 having hypothyroidism and 4 having hyperthyroidism. There was a low prevalence of goiter. The clinical feature of patients with hypo and hyperthyroidism was similar to other reported studies. The commonest aetiology of hypothyroidism was found to be dyshormonogenesis. A host of co-morbidities was observed along with thyroid dysfunction. On follow up with appropriate therapy, most of the children became euthyroid and complications were observed in only a minority. There is a high prevalence of thyroid dysfunction in children in western India and need for similar studies from different regions of the country covering larger population are well appreciated.