Feed-in Tariff (FIT) is the long-term agreement between governments and firms investing in solar energy, where governments guarantee to purchase the energy produced by firms. This research aims to reveal the optimal FIT design for Photovoltaic (PV) investments in Turkey. Choice Experiment based questionnaire was conducted on solar energy firms to investigate the investment preferences and monetary worth of each FIT component for investors. We found that FIT design with longer contract duration creates positive value for PV investments, while low payment amount per kWh, tax policy for imported PV panels, and license fee decrease the attractiveness of PV investments.