The most common procedure to perform a production history matching is to start with a base model and modify reservoir and fluid properties to adjust simulation results with the production history of the field. This paper presents an example of a different procedure. The history matching starts with an uncertainty analysis where several possible models are generated and the models that do not reproduce the behaviour of the reservoir are discarded: 1) allowing E a faster history matching process; 2) increasing confidence in the process; and, 3) adding uncertainty analysis to the production prediction. The methodology starts with a dynamic sensitivity analysis based on simulation of models where uncertain attributes are tested and compared with a base model. The attributes are then selected and combined in a derivative tree. Several models are evaluated and those that do not match the production and pressure history are discarded, reducing uncertainty in prediction of E the behaviour of the reservoir. This methodology was motivated by a reservoir with unexpected behaviour that yielded a difficult history matching when considering the usual procedures. Techniques were developed to analyze reservoir performance and differential pressure maps between zones. New approaches to assess connectivity between zones were used to give alternate structural models to the sensitivity analysis. This methodology may be helpful during the first years of production when uncertainties are still significant and when typical procedures to perform production history matching are unable to j solve the problem efficiently.