In this study, the energy, exergy and economic (3E) analyses were performed for the photovoltaic/thermal collector-assisted heat pump domestic water heating system under two different climatic regions (Hakkari and Trabzon) in Turkey. Designed photovoltaic/thermal collector-assisted heat pump domestic water heating system with a storage tank having larger volume and cross-flow heat exchanger in Turkey can be considered as novelty of this study. The system modelled with the help of TRNSYS simulation code by using real weather data and energy analysis was performed based on year-round simulation results. And then, exergy and economic analyses were obtained based on monthly average temperatures. The system considered in this study was also compared economically with conventional natural gas and electricity water heating systems. According to the results, the maximum energy and annual average exergy efficiencies of the considered system were 68% and 22.3%, respectively, for Hakkari, and 67% and 21.4%, respectively, for Trabzon. Although Hakkari has cold climate conditions, the investigated system had lower energy consumption costs than conventional systems. The annual energy consumption costs of the system for Hakkari and Trabzon were calculated as 67.14$ and 135.75$, respectively. The results bring out that although the investment of the system is feasible for Hakkari, it is not feasible for Trabzon.