This paper quantifies and analyses the impacts of climate change on water availability for hydro generation and land suitability for key crops in three least developed countries in the Greater Mekong Sub-region, namely, Cambodia, Laos and Myanmar. The method used for the climate study is supported by the inter-sectoral model inter-comparison project (ISIMIP database). The recent ISIMIP input dataset, ISIMIP2b, outlines simulation scenarios divided into different emissions pathways (or “Representative Concentration Pathways” known as RCPs). This paper focuses on the two extreme RCPs, specifically RCP2.6 and RCP8.5, which would result in global average temperature increases of approximately 1.6 and 4.3°C respectively. Th analysis concentrates on the difference between the historic period and the end of the century (toward 2100) for the climate conditions for the future. The fuzzy logic global land suitability model has been used to calculate the suitability of the land to support growing crops as well as to investigate how the climate changing could impact this. The analysis shows that quite significant changes in hydro-generation potential can occur depending on the region: Laos and Cambodia show decrease when Myanmar shows increase in output potential between present and RCP2.5 and RCP8.5 respectively. Quite significant increases or decreases in land suitability can occur depending on the region and the crop.