Policy planners face the challenge of formulating suitable agricultural policy by which the required growth in domestic production can be achieved. To attain effective food security policy, one needs reliable empirical knowledge about the degree of responsiveness of factor demand and output supply for commodities. This paper is an attempt in this direction and estimates the factor demand and output supply elasticity for major crops grown in India. These elasticities are used to project the domestic supply of major commodities, viz. rice, wheat, pulse grains, nine major edible oilseeds, and sugarcane under various scenarios with and without acreage expansion and TFP growth. The results of supply projections are compared with the food demand and policy prescription to attain food security is suggested.