The study focuses on the impact of climate change on the hydrology of Mojo River Catchment. The Soil and Water Assessment tool was used for modeling. As the model reveals that NSE =0.74; R2=0.73; PBIAS=1.6 during calibration and NSE=0.65; R2=0.61; PBIAS=1.6 during validation. Here the coordinated regional climate downscaling experiment (CORDEX)-Africa data outputs of GCM models (MPI-M-MPI-ESM-LR, MIROC-MIROC5, CCCma-canEM2, and IPSL-IPSL-CM5A-MR) under RCP4.5 and RCP8.5 scenarios with the Regional Model RCA4 was used. Based on their performance two models were highlighted (MPI-M-MPI-ESM-LR and MIROC-MIROC5) after simulated historical data without bias correction and considering the least PBIAS shows good underlying atmospheric dynamic. For bias correction Quantile mapping was used with Gamma and Normal distribution for precipitation and temperature respectively. Then PBIAS become improved from 43.3% to 5.1% under MPI-M-MPI-ESM-LR and 65.7% to 9.6% under MIROC-MIROC5. Future scenarios climate change was analyzed in three-time periods:2006–2031 near period, 2031–2055 mid-period and 2056-2080 far period. The result MIROC-MIROC5 Model the precipitation increases from +24 to 49% under RCP 4.5 and decreases from 47 to 25 % under 8.5. Similarly, maximum temperature increase from 1.19 to 3.570C under RCP 8.5 and increases from 1 to 1.99 0C under RCP 4.5 this leads to decrease of streamflow from 6.32 m3/s to 5.08 m3/s under near and mid-period in RCP 4.5 but under RCP 8.5 the streamflow become decrease from 6.68,2.64, and 6.31m3/s for the period of near, mid and far future period respectively. For MPI-M-MPI-ESM-LR precipitation increase from 31.9 to 34.8% under RCP 8.5 and decreases from 33.8 to 33.1% under RCP 4.5 but the maximum temperature become increase in both scenarios form 0.45 to 1.8750C under RCP 4.5 and 0.47 to 1.970C under 8.5 and the streamflow become increase from 4.62,4.30 and 7.79 m3/s under RCP 4.5 and 6.68, 2.64 and 6.31m3/s under RCP 8.5 for Near, Mid and Far future Periods respectively. The result of this study indicates that climate will affect the hydrology of the catchment. Due to change streamflow different operations over the catchment should be incorporated with climate change scenarios.