Vellalar is a group of castes in the Indian states of Tamil Nadu, Kerala and northeastern parts of Sri Lanka. The Vellalar are members of several endogamous castes such as the numerically strong Arunattu Vellalar, Chozhia Vellalar, Karkarthar Vellalar, Kongu Vellalar, Thuluva Vellalar and Sri Lankan Vellalar.

The caste system in India is the paradigmatic ethnographic instance of social classification based on castes. It has its origins in ancient India, and was transformed by various ruling elites in medieval, early-modern, and modern India, especially in the aftermath of the collapse of the Mughal Empire and the establishment of the British Raj. It is today the basis of affirmative action programmes in India as enforced through its constitution. The caste system consists of two different concepts, varna and jati, which may be regarded as different levels of analysis of this system.