Aim of this thesis is to overview a methodology for selecting the best fit turbine type which is one of the most important part of run-of-river hydroelectric power plants and to apply this methodology on a case study of Eglence-1 HEPP. Basically, in a Hydopower Plant, Hydro-turbines convert water pressure and its kinetic energy into mechanical shaft power which can be used to drive generators for electrical energy production. There are different turbine types which operates at different rated flows and net heads. The type, geometry and dimensions of a turbine are selected by net head, range of discharges through the turbine, rotational speed, cavitation problems and cost. One of the main disadvantages of run-of-river HEPP is that they have not enough reservoir, but there is a considerable storage capacity in our case scenario. So, by the help of this reservoir, only Francis turbine alternatives have been studied for Eglence-I HEPP. If there would not exist such a reservoir then we had to choose at least one small Pelton type turbine which is more suitable for the flow variations are large and stay in the lower range of design flow. At the last part of thesis, the cost and benefit estimations for a techno-economic evaluation of Eglence-1 HEPP has been discussed to show that this investment earns enough money during its lifetime. All hydroelectric power plants can be considered as tailor-made for each unique application and different alternatives for unique plant can be recommended for various operating conditions.