Aim: Adding platelet-rich plasm (PRP) or mesenchymal stem cells are the most accepted methods to increase fat graft’s permanence. However, there is no consensus on timing and whether the effect of stem cells or PRP is observed more in the recipient area or in the donor area. It is aimed to present the application method and localization of PRP to be combined with fat graft to increase the survival. Material and Methods: in vitro part: Fat grafts were kept in a medium containing PRP. Cell output from the fat graft to the Petri dishes was examined every day. The time to recruit the maximum number of stem cells to the medium was determined (day 10). in vivo part: Eight group of rats were received PRP in different concentrations either to recipient or donor areas of fat grafts. After ten days, fat grafts were transferred to the recipient area. Ninety days after the transfer, histopathological examination and immunohistochemical staining were performed. Results: The group which had received the full-dose PRP to the recipient area showed the highest cellular integrity and vascularity (p< 0.05). Vascularity was superior in the half-dose PRP group compared to the control group (p< 0.05); cellular integrity did not increase. Donor site groups did not show increase in cellular integrity. Conclusion: Although PRP starts to increase fat graft permanence by increasing vascularity, it acts by preserving the cellular integrity of the fat cells as the concentrations increase. The PRP injection to the recipient area 10 days before fat grafting may provide higher survival rates.