BACKGROUND:: Growth hormone may act directly on the peripheral tissues such as cartilage, bone, and adipose tissue, etc., and it can promote fracture healing. OBJECTIVE:: To observe the therapeutic effects of recombinant human growth hormone on small-segment radial bone defects in rabbits. METHODS:: Twenty radial bone defect models were made in 10 New Zealand rabbit forelimbs and were randomly divided into treatment and control groups. The treatment group was subcutaneously injected recombinant human growth hormone after the operation for 2 weeks; in the same method and duration, the control group was injected the same amount of isotonic saline as a placebo. RESULTS AND CONCLUSION:: The treatment group was obviously superior to the control group in callus growth, differentiation of cell morphology and calcinosis. Blood glucose level of the treatment group was slightly higher than that of the controlled group during the treatment, and recovered when the treatment was finished. These findings indicate that recombinant human growth hormone has an effective treatment effect on fractures as well as bone defects and no side effect is observed.