Due to the severe working circumstances and the lengthy service life anticipated from these structures, choosing suitable materials for penstocks in hydropower plants is a crucial task that demands careful attention. The assessment and choice of penstock materials in hydropower plants is the main focus of this study's use of the EDAS (Evaluation based on Distance from Average Solution) approach. The EDAS technique optimises the decision-making process by combining the benefits of objective as well as subjective criteria. Introduction: To ensure the effective and consistent operation of these structures, it is essential to use the right elements for penstocks in hydropower plants. Penstocks are crucial parts that transport highly pressurised water from the reservoir to the turbines, where the energy is captured to produce power. The selection of penstock materials is crucial in determining the durability and efficiency of the hydropower plant due to the rigorous operating circumstances, such as high pressures, turbulent flow, and probable exposure to corrosion. His research aims to develop the methods for choosing penstock materials, ensuring the efficient and dependable operation of hydropower plants in spite of difficult environmental circumstances and long lifespan expectations. Research significance: In order to improve durability, operational efficacy, affordability, environmental sustainability, and safety, penstock material research is essential for hydropower plants. The results of this type of study can help the industry make decisions that maximise the efficiency and durability of hydropower facilities. Method: Using the EDAS technique, decision-makers can objectively assess and rank alternatives while methodically taking into account a variety of criteria. It aids in the facilitation of informed decision-making in difficult situations by taking into consideration both the relevance of criteria and the distances from the typical solution. Alternate parameters: Poly vinyl chloride (PVC), High-density polyethylene (HDPE), Glass reinforced plastic (GRP), Mild steel (MS) Evaluation parameters: Yield strength (YS), Life (L), Thickness (T), Material cost(C), Maintenance cost (MC). GRP got 1st rank, MS got 2nd rank, PVC got 3rd rank and HDPE got 3rd rank. GRP got 1st rank with less compensation.