Dairying plays a greater role in economic life of marginal farmers and landless labourers. As a supplementary enterprise to crop production, it constitutes a significant source of augmenting income in the rural sector in general and for weaker section in particular. The paper examines the cost incurred and profit generated by milk producers belonging to weaker section viz., marginal farmers and landless labourers in Bichpuri block of Agra district (UP). The overall per family average number of milch animals were 3.0, being 3.2 in case of marginal farmers and 2.8 in case of landless labourers. Of the total milch animals about 87 percent were buffaloes and 13 percent were cows. The overall per family total maintenance cost worked out to about Rs 35805. Of this, fixed cost accounted for about Rs 8535 or 24 percent and variable cost for about Rs 27270 or 76 percent.The overall return per rupee of investment came to Rs 1.30. Category-wise it was Rs 1.29 in case of marginal farmers and Rs 1.31 in case of landless labourers.