Objective: To investigate the effects of recombinant human basicfibroblast growth factor (rhbFGF) on the cell proliferation during mandibular fracture healing in rabbits.Methods: The complex of rhbFGF and bovine type I collagen was implanted into the mandibular fracture site under periosteum of the animal. The whole mandible was harvested at 7, 14, 28, 56 and 84 days respectively after operation. The expression of proliferating cell nuclear antigen (PCNA) in callus was examined with immunohistochemical staining.Results: PCNA-positive cells in callus in the rhbFGF-treated group on days 7 and 14 were more than that in the control group (P<0.01).Conclusions: It indicates that rhbFGF can stimulate cell proliferation during mandibular fracture healing in rabbits.