The accuracy of any decision making model depends mainly on the performance in estimation of the priority of each factors in respect to the objective. Multi-criteria decision making (MCDM) offers a feasible option in this regard. The priority value which is determined by the MCDM can differentiate the factor based on their degree of importance with respect to the decision objective. But the problem different ranking results are very sensitive to the changes in attribute weights and difficult to understanding of scale would be a ranking order or a ratio scale by decision maker (DM). In this present study tries to overcome this two disadvantage of MCDM. For overcoming this weakness of MCDM, first time introduce a novel MCDM namely Harmonic Mean Hierarchy Process (HMHP). This new MCDM technique used to solve multi criteria decision making (MCDM) problem. These new methods first time apply for estimate the efficiency of HPP. According to the result selected Efficiency of turbine to be the most influential parameter for efficiency performance of HPP. Also this problem solve by some existing MCDM techniques for verifying the result, which is solved by HMHP.