**Abstract**

Sunflower (*Helianthus annuus* L.) is the main raw material used to produce oil for consumption and oilseed in Turkey; however, its production is not sufficient, even for only domestic consumption. Therefore, studies were needed to determine how to increase both the production area and yield in Turkey. The aim of the study was to evaluate the possible effects of climate changes on future sunflower yield. A total of 29 provinces with intense sunflower cultivation during years of 1985–2014 were evaluated. Sunflower production values and meteorological data, which belong to years of 1985–2014, on climate projections, based on HadGEM2-ES Global Climate Model and RCP8.5 scenario that cover period of 2016–2099, were used as material. In the first part of the study, linear regression analyses were conducted between the observation and production data using the least squares method. In the second part, the possible effects of climate changes on sunflower yield for 2016–2040, 2041–2070, and 2071–2099 were determined using regression equations and climate projection data. Projections indicate that decreases in yield are expected, especially in the second half of this century. In Tekirdag and Konya provinces, where there is intensive sunflower cultivation, severe decreases in yield are expected for all studied periods.

**Keywords:** climate change, sunflower yield, regression analysis, HadGEM2-ES, RCP8.5
