Objectives: Polycaprolactone-20% tricalcium phosphate (PCL-TCP) polymers allow for cellular adherence and differentiation and are adequate scaffolds for bone regeneration in tissue engineering strategies. The placenta contains multipotent stem cells. This study evaluated the utility of placenta derived mesenchymal stem cells (PDMSCs) seeded onto PCL-TCP scaffolds for bone tissue engineering. Materials and Methods: PDMSCs were isolated from placenta. PCL-TCP scaffolds with PDMSCs were implanted in full-thickness mandibular bone defects (2×2 cm) in minipigs. In the first experimental group, defects were treated with amnion-derived MSCs placed onto the scaffold, whereas in the second experimental group, defects were treated with deciduas-derived MSCs placed onto the scaffold. As a control, a third defect was treated with the scaffold only. Histological and radiographic examinations were performed twelve weeks post-implantation. Results: Soft radiographic measurements showed that experimental groups had twice the bone density of control group. Experimental groups had a statistically significant increased bone regeneration potential compared to control group in mandibular bone defects in minipigs. Micro CT showed that experimental groups had higher levels of percent of regenerated volume fraction, regenerated bone volumes and regenerated bone surface than control group. The histologic examination revealed the presence of regenerated bone at the central area of defect. Conclusion: PDMSCs seeded into the PCL-TCP scaffolds enhance bone regeneration in mandibular defects. Therefore PCL-TCP scaffold with placenta derived mesenchymal stem cels can increase bone regeneration.