BACKGROUND Hashimoto's Thyroiditis (HT), a synonym of chronic lymphocytic thyroiditis or autoimmune thyroiditis is characterised by Hurthle cell change and infiltration of mature lymphocytes into the follicles. The autoimmune process is believed to begin with the activation of CD4+ T Cells, which initiate the recruitment of autoreactive B-cell that secrete variety of thyroid antibodies. The important of them are anti-thyroglobulin antibody, thyroid peroxidase antibody/anti-microsomal antibody and thyroid stimulating hormone stimulation blocking antibodies. It is the most common form of thyroiditis diagnosed on Fine Needle Aspiration (FNA). Different autoantibodies against thyroglobulin and thyroid peroxidase antigen are clinically most important for diagnosis, which are present in less than 60% and over 90% respectively in patients with Hashimoto's thyroiditis. MATERIALS AND METHODS In view of all the above facts, a combined cytomorphologic and serologic approach in the evaluation of Hashimoto's thyroiditis has been emphasized in our study. The prospective study was conducted in the Department of Pathology, M.K.C.G. Medical College, Berhampur from October 2012 to September 2015. RESULTS Total number of 50 cases of HT were evaluated for cytological features and serological markers. Occurrence of HT was found in maximum 20 to 30 (50%) years of age group. Females are more affected than males with male and female ratio of 1 : 11.5; 28 cases (56%) were hypothyroid, 19 cases (38%) were euthyroid and 3 cases (6%) hyperthyroid. Lymphocytic background was seen in 100% cases, whereas Hurthle cell change and high L : E ratio was observed in 76% of cases. Overall antibody positivity was found in 94% of cases, out of which 60% were AMA positive, both AMA and ATG was positive in 30% cases, whereas both antibodies negative was found to be in 6% cases. CONCLUSION We conclude that HT is common on 2 nd and 3 rd decade of life. Serology is a useful adjunct in diagnosis of HT. Serologically, TPO was found to be a better marker than ATG. In euthyroid patients with negative antibody titre, FNAC is the gold standard to establish diagnosis.