Climate change is a phenomenon most of the world is recently coming to terms with, but unfortunately, the African region is yet to fully understand and prepare for its effects. This study highlights the impact these changes experienced in the Nigerian climate system will have onCrop water requirements (CWR) for optimal productivity. Data were obtained from five global climate modelsnamely CCCMA, MIROC, ICHEC, NOAA and NCC. These data were sourced in Representative Concentration Pathway 8.5 (RCP8. 5) for the 36 states including the Federal Capital Territory (FCT). The data length varies from 1985–2100 for historical, present and future periods. Penman Monteith evapotranspiration (ETo) calculator was used to determine CWR. Trend analysis was carried out on the rainfall, temperature data, and the CWR. This analysis showed a projected slight increase in rainfall and significant increments in temperature varying in the range of 131.18 mm to 135.3 mm and 27.2oC to 29.1oC for rainfall and temperature respectively. Results also showed that CWR will increase in future and it correlated strongly with temperature and weakly with rainfall. This result implies that temperature affects CWR more withit driving up the water use of cassava, rice and soybean, thereby leading to increase in yield if adequate water is available as well as coupled with proper management practices. The study has concluded that CWR will increase as the years go by and is higher in states with higher latitudes; it is therefore recommended that farmers' crop production activities should be adapted to maximize available water efficiently.