Due to small and marginal land holdings and fluctuated nature of rainfall , farmers are unable to get income round the year. In this direction , cultivation of Oyster mushroom as subsidiary agri-based enterprise is the best solution for getting income Mushroom cultivation is highly remunerative enterprise with quick return in a short span of time. Oyster mushroom can grow by using materials from agriculture. Since four years , we established Mushroom training and production unit in college campus at pipri under which ,we are conducting skill development trainings to farmers , women farmers, rural youth and for students. In this context, the present investigation was undertaken for 20 beds to study the cost and benefit of mushroom production at domestic level and to analysis profitability of mushroom cultivation. We used easy technology, minimum space and low cost operation. After the analysis of all costs incurred, we found that, the total cost required for 20 bag or beds was Rs. 677.00 ( including variable cost and fixed cost)and average cost required for per bed is Rs. 33.85 ( round Rs. 34/). Production per bed received 1.00 kg. Total production received from 20 beds was 20.00 kg , and the price is @ 200 per Kg. hence total production received from 20 beds is Rs. 4000.00/- average production from per beds received Rs.200.00 Net profit received from 20 beds is Rs. 3323/- and per bed net profit received Rs.166.00/- It is clearly seen that, each bed given Rs. 166.00 as a profit. It is concluded that, mushroom enterprise is required low cost , easy technology and minimum space to cultivate . It was taken only 40-45 days to complete one phase of 20 beds cultivation. One youth or woman can cultivate 50 beds at a time This enterprise is highly remunerative to farmers as subsidiary agri-business. It is sustainable enterprise for rural youths and women. It is a part time job venture to all kinds of rural and urban youths.