Among dozens or hundreds of alternatives, choosing those which should make up the projects portfolio of an organization and which priority level is a complex multi-criteria decision matter. This work aims to apply a management model of projects portfolio, using the AHP (Analytic Hierarchy Process) method and an integrated integer program. Another purpose is to validate and evaluate the importance and use of the model to help the decision-making related to the selection, prioritization and balance of projects. Thus, such a model was applied to select and prioritize the projects of a company in the chemical sector, chosen as the unit of analysis. The different scenarios obtained from the decision-making model proposed were compared to the real scenario of the company. Since the author interacted in the company's decision-making not just as an observer, to carry out the study the research-action method was chosen, since it is the most suitable for the case. It could be noticed that the use of the model contributed first, to the strategic alignment of the projects, enabling the exchange of knowledge between the company representatives; secondly, it allows the simulation of strategic scenarios in real time, as well as verifying the impact of the projects portfolio; thirdly, it prioritizes the projects in a justifiable and structural manner through an established mathematical model; finally, it enables to allocate the resources based on priorities.