Distributions of aquifers and groundwater yields are studied using a well database to evaluate the potential installation of the groundwater heat pump systems in the Nobi plain of Gifu prefecture. The distribution of two aquifers is deduced from that of well screens that are getting deep gradually toward the south.The distribution of the groundwater yields indicates that the groundwater heat pump systems using pre-existing wells have a potential installation in the whole of the study area. The distribution of the groundwater yields drawn from the aquifers shallower than 50m depth shows that the northern part of the study area is a suitable area for the installation of the groundwater heat pumps with a well drilling.The potential installation of the groundwater heat pump systems using the groundwater drawn from the total depth and shallower than 50m depth are 52.9% and 26.0% for the houses in the study area, respectively.These results suggest that the study area has a large potential for the installation of the groundwater heat pump systems.