This study presents the rehabilitation project for the Francis turbine runner of Kepez 1 Hydroelectric Power Plant (HEPP) in Antalya, Turkey. The aim of rehabilitation is to increase the power and efficiency of the plant and solve the existing problems such as cavitation. Initially, the head and flow rate of the turbine are estimated. Within the scope of this study, the design parameters which are necessary to obtain better cavitation characteristics and higher power and efficiency, are determined and computational fluid dynamics (CFD) is utilized to design a new runner geometry for better performance. The results of the CFD simulations are compared to the simulation results of the existing runner geometry which was obtained from the plant and scanned using laser scanning. The results show that cavitation characteristics and the efficiency, as well as the power of the HEPP are improved.