This study investigated the effects of crown material, post material, and post geometry on stress distribution in molar tooth restored with post-core crown. A three-dimensional solid model consisting of the mandibular second molar tooth, periodontal ligament, cortical bone, and spongy bone was generated. Finite element analysis results showed that prefabricated posts with a composite resin core increased stress concentration at the cementoenamel junction (CEJ), while cast posts induced high stress at post-dentin interface. Increase in the elastic modulus of crown material also increased the stress concentration, especially at CEJ.