Crop yield data were obtained from Kwara State Agricultural Development Project (KWADP), Ilorin and National Bureau of Statistics (NBS), Lagos on the crops considered in this study, while climate data were sourced from the Nigeria Meteorological Agency (NIMET), Oshodi, Lagos and National Bureau of Statistics (NBS), Lagos for a decade (2002 - 2011). These data were analyzed using SPSS 16.0 and Microsft Excel in order to evaluate the impact of climate on the yield on reference crops in Kwara State, Nigeria. Multiple regression, trend analysis, correlation analytical and ANOVA techniques were used to analyze the data. This study was necessitated by the decline observed in the production of cash crops in the state. The result obtained from the analysis carried out on the output per hectare showed that the impact of climate on crop yield was significant for maize and rice yield at 95% probability level while the impact of climate on the yield of millet, sorghum and cowpea was insignificant. As a result, it is recommended that investment should be made to intensify the cultivation of crops on which climate had no significant impact on their yield.
Key words: Agriculture, climate, grain-crops, yield, decade.