Sensitivity and uncertainty of hydrogeological model predictions should be carefully analyzed before they are utilized as a decision making aid in the planning and management of water resources. In this work a global parameter sensitivity analysis is conducted using the FAST procedure (Fourier Sensitivity Amplitude Test) linked to the MODFLOW computational environment. Finally, the latin hypercube sampling methodology is subsequently implemented to investigate uncertainty of model estimates, accounting for errors due to model structure, input data and model parameters. To demonstrate their effectiveness, the parameter identification, parameter estimation, model verification and uncertainty analysis techniques were applied to a real case study in Spain.