This work was conducted by ab initio calculations in order to study the 2H-MoS2 structure on MgO system. The study of the interaction with the surface was made by analyzing Bader, PDOS and electronic density difference, varying the number of layers. Moreover, the comparison of the vacancy formation energy for these systems was obtained. We verified that the vacancies formation in the system composed of three monolayers sulfide is more favorable and also that the support contributes to electronic stability. (C) 2015 Elsevier B.V. All rights reserved.