In Tunisia, geothermal water constitutes the main water resources potential for agriculture use in the south. However, vulnerability of crops to damage by high temperatures has driven the use of cooling towers for dropping temperature to an appropriate level for crop irrigation. Cross flow mechanical cooling towers widely spreads all over the south region of the country. These towers are sized empirically and present several problems in regard to operation and electrical energy consumption. This paper presents experimental results of tests performed on geothermal water cross-flow cooling tower in the south of Tunisia. The aim of the work has been to determine experimentally the governing parameters, their effects on cooling performances and the cooling tower characteristics. The obtained results are very important since they will contribute to design cooling towers with high efficiency, energy saving and adapted to the climate conditions of the south of Tunisia.