Dairy farming occupies a notable place in the agricultural economy of India and milk and milk products are the second largest contributor to Gross National Product (GNP) and income from dairy farming contributes nearly a third of the rural household’s gross income. Tamil Nadu is one of the leading milk producing state in the country, the other states being Uttar Pradesh, Madhya Pradesh, Punjab, Rajasthan, Gujarat, Maharashtra, Andhra Pradesh and Hariyana. Paradoxically, however, the milk production in Tamil Nadu is witnessing a declining trend in recent years due to low productivity of the milch animals, which have been attributed to poor genetic status, non-availability of proper nutrition, poor quality of management and so forth. The rural producers are not only ignorant of the qualitative aspects of the enterprises but even unmindful of the production capabilities of their animals. The knowledge of the economics of milk production in the rural areas would be of immense help for planning for improving of dairy animals and in formulating policies for improving the profitability of the enterprise. The present study is, an attempt to compare the cost and returns of milk production across different farm groups and to analyse the resource – use efficiency of dairy enterprises in Coimbatore. The study was based on primary data which was compiled by administering a pretested interview schedule to 150 randomly selected dairy owners residing in Mayilampatty village in Coimbatore District. The data collected relate to the period January to December 2009. The respondents were classified into 3 groups (small farmer, medium farmer and large farmers) based on the size of the farms owned by them. The study would highlight the cost and returns of milk production. Cost function and the production function will be analysed. Added to this resource productivity and resource use efficiency will be handled.