The sensitivity of subtropical African river basins to possible future climate change is a matter of some concern. In Ivory Coast, previous works on climate change impacts predict a decrease in annual average water resource by the 2080s between 6.9% and 8.4%. This is a potentially serious issue because of a series of historical resource management decisions that have increased dependence upon water use, such as through major dam building schemes. This paper focuses upon the Buyo Lake catchment, a central resource for the Ivorian people with the aim of providing future water resource scenarios, under climate change so as to develop appropriate adaptation policies. The study applied simulations from the UKMO climate model, HadGEM1 from the ENSEMBLES project 2009, with the A1B emissions scenario in continuous simulation. Daily climate data such as rainfall, temperature, wind speed and relative humidity were input to the SWAT hydrological model. The simulations were performed after model calibration. Analysis focuses on the periods 1950-1979 (baseline), 2035-2064 (2050 horizon) and 2064-2093 (2080 horizon).The results showed that the entire basin of Buyo could experience a serious temperature elevation of +1.34