To evaluate the effect of autologous platelet rich plasma (PRP) for healing of femoral bone defect in dogs. 24 adult mongrel dogs were used in this study, a 2 - cm cortical segment of the Femur was osteotomised, and then fixed with a 8-hole dynamic-compression plate. The animals were divided into two groups; group A (n=12) control group and group B (n=12)
PRP group. Dogs were euthanized at 2, 4, 8 and 12 weeks. The specimens were assessed for bone union by clinical, radiographical and histological examinations. It was found that, osteoid bridging the gap at femur defect was noted in all specimens in the PRP groups at week 8 and12 while, in control group there was a minimal tissue reaction at the bony edges of the defect. In conclusion PRP increased bone healing in early stage.