Though farmers` feed various vegetative biomass such as fresh, dry or preserved form for feeding livestock, the productivity was found low compared to the world average. As, fodder crops are found as a negligible crop, due importance is not given for cultivation of fodder crops in the field. Along, with this water is also found to be an important factor for not cultivating fodder crops. Fodder cowpea is one of the important fodder crops and fodder cowpea is deprived of resources mostly during cultivation due to its shorter duration and nitrogen fixing ability. As domestic sewage water contains nutrients required for plant growth and development, the experiment was an attempt to understand the response of fodder cowpea to realise its productivity and its effect on soil fertility. A pot experiment with fodder cowpea was laid out in complete randomized block design during rabi season, 2019 and 2020 to assess the effect of different sources of irrigation water on the growth, productivity, nutrient uptake of fodder cowpea and soil fertility after harvest of fodder cowpea. The irrigation treatments consist of application of ground water, domestic sewage water, ground water and domestic sewage water alternatively. Investigation resulted in higher growth, productivity and nutrient uptake of fodder cowpea and improvement in post-harvest soil available nutrients with application of domestic sewage water.