Objective To investigate the accelerating role of recombinant human parathyroid hormone (PTH) in bone fracture repair. Methods 2-month old male Sprague-Dawley rats underwent closed unilateral femoral fracture and intramedullary nail fixation. The rats were divided into 2 equal groups randomly:the treatment group receiving subcutaneous injection of rhPTH(1-34) 10 μg/(kg·d) immediately after operation and for 2,7,14,21 and 42 d,respectively, and the control group receiving subcutaneous injection of normal saline in the same volume. X-ray and micro-CT were conducted at 2, 7, 14, 21 and 42 days after surgery. Results The continuity of porosis between fracture sides was better and fracture line has been blurred in the PTH-treated group at 21 days after fracture compared with the control group, the bone volume (BV),BV/TV, bone mineral density(BMD)and trabecular pattern factor (Tb.Pf) were significantly higher, and trabecular separation (Tb.Sp) and degree of anisotropy (DA) were significantly lower in the PTH-treated group at 42 days after fracture. Conclusions Our findings suggest that a low dose recombinant human parathyroid hormone can accelerate the bone fracture healing, probably through improving the BV, BV/TV, Tb.P and BMD, and decreasing the Tb.Sp and DA..