Fuente Grande spring is the main natural discharge point of the carbonate aquifer system of the Sierra de la Alfaguara (Granada, Spain). The hydrodynamic and hydrochemical responses of this spring, with respect to precipitations recorded during the study period (2000-2002), show that the system drained is a fissured system, because slow and little increases in the outflow of the spring, accompanied of a scanty dilution process. The analysis of depletion curves shows that this is a slow process; moreover, the temporal variation of the electrical conductivity of the water and the variation coefficient of this parameter, confirm the low karstification degree of the aquifer