GSHP (Ground source heat pump) system is a promising technology for cooling and heating building in the world. Regrettably, this technology is still not available in Tunisia and it is time to test the GSHP systems in our country. For this purpose, two experimental systems are performed at the Research and Technology Center of Energy (CRTEn), in Borj Cedria, northern Tunisia. Firstly, to evaluate optimal parameters of the GHE (ground heat exchanger), the performance of the GHE with horizontal configuration was analyzed experimentally and analytically. The effect of various parameters such as mass flow rate of circulating water, length, buried depth and inlet temperature of the GHE on the heat exchange rate were examined. Second, water-to-water GSCS (Ground Source Cooling System) with HGHE (Horizontal Ground Heat Exchanger) was performed. The results obtained from this experimental study, are used to evaluate the COPhp (coefficient of performance of the heat pump) and the COPsys (coefficient of performance of the overall system) of the GSCS, which are ranged between 3.8-4.5 and 2.3-2.7, respectively. The results showed that the utilization of the ground source heat pump is appropriated for cooling building in Tunisia, which is characterized by a hot climate. (C) 2013 Elsevier Ltd. All rights reserved.