This longitudinal study was conducted at a teaching hospital in a metropolitan city in Western India on 42 patients (33 girls: 78.57% and 9 boys: 21.43%) who had confirmed diagnosis of autoimmune thyroiditis. The mean age of girls was 9.48 +/– 2.83 years, while that for boys was 9.67 +/– 2.74 years. Nearly 50% of patients had family history of thyroid dysfunction. The mothers of 17 patients were affected with hypothyroidism and 5 out of these 17 mothers (29.41%) had thyroid antibodies. Paternal history of thyroid dysfunction was reported in 4 families and in one family; there was a history of thyrotoxicosis in father and grandfather. Goitre was the most frequent clinical finding; other common findings were dry skin, short stature and bradycardia. On follow–up, all children had improved clinical and biochemical parameters. Catch–up growth was observed, with growth rate increasing 2 to 3 fold above the normal for age.