The aim of this research is to simulate the future water balance of the silwani watershed, Jharkhand, India under the combined effect of land use and climate change based on Soil and Water Assessment Tool (SWAT) and cellular automata (CA) Markov models. The future climate prediction was done based on daily bias-corrected datasets of INMCM5 climate model with Shared Socio-economic Pathway585 (SSP585) which represent the fossil fuelled development of the world. After successful model run, water balance components like surface runoff, groundwater contribution to stream flow and ET were simulated. The expected change in LULC between years 2020 to 2030 strongly contributed to increasing in groundwater contribution to stream flow whereas decrease in surface runoff. The result of this research work helps the planner for planning of any watershed for future conservation.