The modeling of rock mechanical behavior is essential to develop wellbore stability studies. In that sense, estimating rock mechanical properties and the in situ stress field are required tasks to understand the resulting deformations. In order to evaluate drilling effects on rock mechanical behavior, numerical models were constructed to represent the most commonly described rocks in the pre-salt session of an oil field located in Santos basin. Firstly, the author introduced the wellbore retro-analysis methodology proposed for this study. The technique was validated against real wellbore data with a fairly good match. Thereafter, a test model was conducted on a synthetic stratigraphy considering the typical occurrence of pre-salt rocks and the expected in situ stress field, as determined by correlated wellbores data. The numerical results of this test were compared to the data acquired in a local oil well and seemed to provide a reasonable fit, corroborating the applied technique. It was possible to evaluate typical pre-salt rock mechanical behavior by using correlation wellbores and still predict possible wellbore geomechanical problems during the drilling phase.