This study investigates the impacts of climatic change on global markets of maize, rice, and wheat. The first step is to combine the Crop Yield Model estimated results and climate factors data predicted from five climate models (i.e. hadcm3, MIROC3_2_MEDRES, ECHAM5,CSIRO-MK30, and CNRM_CM3), and with the assumption that future world is in IPCC (2007) A1B scenario. Under such assumptions, we estimate the production impacts in 2030, 2040, and 2050. Moreover, using Global Trade Analysis Model (GTAP) and its data set we can further assess the economic impacts on food price, productivity, GDP, and social welfare. Simulation results show that the negative impacts of future climate change are imposing serious effects on the production of maize, rice, and wheat. Moreover, results also indicate that adverse impacts on GDP and social welfare in various countries can be seen. Among these countries, India, Mexico, and Indonesia are experiencing larger magnitude of adverse impacts on GDP in three out of five climate models. On the other hand, the most significant negative effect on social welfare is in China, India, and Mexico.