In this study, we assessed the climate change impact on water resources availability and hydropower energy yield from the murum Dam in Sarawak state of Malaysia. Precipitation ensembles of three general circulation models from coupled model Intercomparison Project Phase 5 (cmIP5) were used to simulate daily inflows at murum Dam for the historical period of 1976-2015 and for the future period of 2011-2100 under two future scenarios (rcP4.5 and rcP8.5). a rainfall-runoff model was developed using australian Water balance model approach to simulate river inflows at murum Dam. reservoir operation model was developed using hec-resSim to simulate the operation for murum reservoir under the historical and future projected inflows. It is noted that the mean river inflow at murum Dam would increase by 4 and 11 during 2080s under rcP4.5 and rcP8.5, respectively. Similar results are noted while simulating the murum reservoir operation; it is noted that the average annual energy from murum hydroelectric Plant would increase by 5 and 12 during 2080s under rcP4.5 and rcP8.5, respectively. © 2019 WIT Press