This work presents the stress distribution in a root dentin restored by means of endodontic posts made of different materials. Two 2-D models of a maxillary central incisor with thin dentin walls, including its support elements were created making use of AutoCAD 2000 software. Model 1 represented a pulpless tooth, filled with guta-percha and restored adopting a cast post and an all-ceramic crown. This model was used for the analysis of gold and zirconia posts. Model 2 was similar to the first one, but adopted a cylindrical post centralized in the root cavity and filled with composite resin. This model represented the prefabricated posts made of glass fiber and carbon fiber. The numerical simulation was carried out by the ANSYS 7.0 software and the models were loaded with 100 N applied at the angles of 45 degrees and 180 degrees with respect to the longitudinal tooth axis. The results showed that, in all models, the stresses were concentrated at the apical end of the posts, indicating that this region is a critical root region and that the post s geometry can influence its risk of fracture. With regard to the cast posts, characterized by a higher elastic stiffness, a greater stress level was concentrated at the post, preserving the root dentin at the medium and cervical regions and, therefore, being considered more efficient in the case of worn roots. The models based on glass fiber and carbon fiber showed a homogenous stress distribution along the tooth as well lower stress level at the post, preserving the restoring material. However, the root dentin was subjected to higher mechanical loading.