In order to fulfill requirements of people due to increase in population, all countries are developing new production strategies and plans for using more efficient sources. Climate change and agricultural drought are the most important environmental factors effecting agricultural production in the world. Aim of this study was determining the possible effects of climate changes on tomato (Solanum lycopersicum L.) production under created future climate conditions in the Mediterranean Region of Türkiye. For this purpose, 2 yr (2014-2015) field experiment was conducted for calibration and validation of Cropgro model of Decision Support System for Agrotechnology Transfer (DSSAT) version 4.5, Reference (1961-1990) and future (2001-2099) years climate data which were calibrated for Seyhan Basin of the International Centre for Theoretical Physics (ICTP) Regional Climate Model system version 3 (RegCM3) were used to obtain future climate conditions by pseudo-warming downscaling technique. According to the results that precipitation will decrease in a range of 21-25% also minimum and maximum temperatures will increase in a range of 16-29% in the both experiment years respectively. Cropgro of DSSAT model simulated that tomato yield will decrease about 16-17% while increase biomass in a range of 30-32% depending on the climate change effects in the future. It is recommended to compare the model outputs with obtained field data in order for the model to make more appropriate estimations. DSSAT crop simulation models (CSM) can be used in agronomy studies to estimate yield and growth parameters.