||These days, Energy problem has been a serious issue due to continuing high oil price and exhaustion of resource. Especially, the energy in apartment house like dormitory has been consumed recklessly. As a solution for this energy problem, it is urgent to applicate alternative energy, that is, renewable energy. In this sense, this study analyzed economic evaluation of geothermal heat pump system. First, comparison between existing gas heat pump system and geothermal heat pump system was preceded and follow the analysis of annual energy reduction amount according to early investment prices and operation expenses. As a result, it was show that geothermal heat pump system used only 13% of existing system energy expense. This study will attribute to inform the excellence of geothermal heat pump system and be used as source materials for the application of apartment house in.