To evaluate the effect of platelet rich plasma(PRP) and platelet rich fibrin(PRF) on bone defects with autogenous bone graft and control(no treatment) in the same rabbit calvaria. Four rabbits were included in prospective study. In each rabbit, four equal 8 mm diameter cranial bone defects were made with trephine drill and it was immediately grafted with PRP, PRF, autogenous bone and one defect was remained with no treatment(control). The defects were evaluated by cone beam CT at 2, 4, 6 and 8 weeks. At 8 weeks, rabbits were sacrificed. Soft X-ray with step-wedge calibration and histologic process were taken with sacrificed rabbits for radiomorphometric and histomorphometric analysis. Radiomorphometrically and histomorphometrically, the results showed a significant increase in bone formation on autogenous bone graft group. Both PRP and PRF groups showed significant increase as compared with the control group. There was no significant difference between PRP group and PRF group. Significant improved bone formation was seen with the addition of PRP or PRF on non-critical sized defects in the rabbit cranial model. And PRF group showed more uniform and similar result compared with PRP group. It is reasonable to think that PRP and PRF can promote bone regeneration. Also, PRF can replace PRP according to good uniform result and simple manipulation.