Introduction The preservation of tooth structure during cavity preparation is crucial for maintaining tooth strength and longevity of restorations. The biomechanical behavior of teeth, especially those with mesio-occlusal-distal (MOD) cavity preparations, is significantly affected by the extent of cavity preparation and the type of restorative treatment employed. The aim of the current study was to evaluate and analyze the stress distribution seen in the mandibular molar with MOD cavity when restored with transverse post, using finite element analysis (FEA). Materials and methodology FEA was utilized to evaluate stress distribution in an endodontically treated mandibular first molar with MOD cavity preparation, restored using a transverse post and composite restoration. Three-dimensional models incorporating the tooth and the surrounding structures, along with the transverse post and composite restoration, were constructed based on known biomechanical properties. After meshing the models, loads were defined on the buccal and lingual cusps with a constant value of 600N and at an angle of 45 degrees. Preprocessing involved model preparation followed by postprocessing to obtain results representing the degree and type of stress distribution. Results FEA simulations revealed the distribution of stress within the tooth structure under functional occlusal forces. The transverse post system effectively reinforced the tooth by deflecting incident forces and providing uniform stress distribution. von Mises stresses were analyzed to assess the likelihood of material failure. The distribution of the stress in the restored tooth model was comparable to that seen in the intact model. Conclusion Transverse postalong with composite restoration provides a conservative and cost-effective alternative to fullcoverage crowns while providing a functional and aesthetic outcome. Further research and clinical studies are warranted to validate these findings and optimize the clinical application of transverse post systems in restorative dentistry.