Papillary thyroid carcinoma is one of most common malignant thyroid tumor, while medullary thyroid carcinoma is relatively rare. Both these tumors have different cell of origin and clinical implications. Synchronous papillary and medullary thyroid carcinomas are rare and show medullary component with positivity for calcitonin and component of papillary carcinoma with positivity for thyroglobulin. We describe our experience of three patients with synchronous medullary and papillary thyroid carcinoma detected over a period of 22 years from a tertiary care referral center in India. Numerous hypothesis are proposed to understand the mechanism of this co–occurrence. True mixed carcinoma with dual expression of thyroglobulin and calcitonin are a controversial entity, but all three of our cases show distinct and well defined population of medullary and papillary carcinoma, supporting a different cell of origin of both tumors. It is a diagnostically challenging and important entity in the evaluation of thyroid tumors.