A preliminary hydrogeological investigation of the Roccamonfina Caldera was conducted in order to increase the local knowledge of the multilayer aquifer hosted within the ignimbrite deposits. Three aquifer levels were distinguished according to stratigraphic data and according to the bottom well depth. The aquifer levels recharge punctual and linear springs with a total natural discharge of about 200 L/s. A preliminary groundwater recharge of about 300 L/s was calculated using the effective infiltration value (368 mm/y) suggested by Boni et al. (1986). A more detailed groundwater budget will be calculated afterwards, using the distributed method. Groundwater effective recharge will be calculated taking into account data about rainfall, land use, runoff and withdrawals values.