Osteoporosis is the most prevalent metabolic bone disease and is characterized by diminished bone strength predisposing to an increased risk of fracture. We investigated the effects of the extract from Acyranthes Radix on the progress of bone loss in ovariectomized rats for 6 weeks. Female Sprague-Dawley 40 rats of 3-4 weeks, weight 200 ${pm}$ 10g were divided into two groups including the sham operation group(8 rats) and ovariectomy group(32 rats). The dose-dependent effect of Acyranthes Radix extract on bone mineral density and biochemical testing was assessed in ovariectomized rat. Body weights were increased in all groups was higher in experimental group than sham operation group. The level of bone mineral density, GPT, and serum P concentration, ALP were increased experimental group, but a little increase in sham operation group at same period. This longitudinal study result made conclusion that Acyranthes Radix extract treatment appeared to improve the osteoporosis delaying the progression to the osteoporotic process in rats.