A farmer uses various inputs in varying quantity depending on a type of crop grown, type of soil and type of input, etc. Therefore, it is very much pertinent that an optimum inputs mix is achieved by a farmer so as to obtain the best possible production in agriculture. The cost of cultivation or the cost of production of any crop helps the farmers in judging the profitability of the crop and accordingly changing the cropping pattern. The cost and returns of cotton cultivation have, therefore, been estimated in the present study. The cost of cultivation of cotton incurred by the sample farmers during the reference year 2013-14 included home produced and purchased impulses. The impulses implemented in the cotton varieties are seed, FYM, oil cakes, chemical/organic fertilizers, irrigation, pesticides, tractor and bullock labour, human labour, land revenue, interest on working capital and fixed capital, rental value of owned land etc. The output-input ratio over Cost C2 was 1.42 for large farmers, followed by 1.33 for medium farmers and 1.26 for small farmers with the overall average of 1.34. This indicates that on an average one rupee invested in the cultivation of cotton earned Rs. 1.34. The output-input ratio over Cost C2 had increased with increase in farm size groups. It is clearly shows that the relationship between output-input ratio over Cost C2 and farm size groups were positively related with the size of landholding groups. The co-efficient of determination (R²) turned out to be significant at 1 per cent level, indicating that the included variables explained between 74 to 89 per cent of variation in the production of cotton for all the categories of farmers. The inputs, area under cotton, seed, human labour, manures and fertilizers, pesticides and irrigation are having significant influence on the output of cotton for all the categories of sample farmers except the input variable education.