Pulses are the major sources of dietary protein in the vegetarian diet in our country. Besides being a rich source of protein, they maintain soil fertility through biological nitrogen fixation in soil and thus play a vital role in furthering sustainable agriculture. The study attempts to focus on the yield constraints of small and large farmers producing black and green grams of pulses in Tuticorin District. The proportionate random sampling technique has been adopted to select 150 each of pulses cultivating farmers from 12 villages. The data relates to the month of February 2012. The Garrett’s ranking technique was applied to identify the major constraints to the attainment of potential yield and it was found that severity of disease and pest attacks and water shortage were identified as major constraints for both Large and Small farmers cultivating Black Gram of pulses . In the case Green Gram, Large farmers have reported that the inadequate credit facilities and water shortage to be the main constraints to maximum yield. Similarly, the majority of the Small farmers have identified water shortage as a major constraint.Thus, it may be concluded that severity of diseases, inadequate credit facilities and water shortage were identified as major constraints in the study area. 

Key words: pulses, protein, soil fertility, yield, constraints, Garrett’s ranking.