The aim of this investigation was to examine the effects of serum alkaline phosphatase, phosphorous, calcium and bone mineral density in P diet on osteoporosis induced by ovariectomy in rats. Female Sprague-Dawely 20 rats of weighting 249±29g, were divided into four groups including the sham operation groups (5 heads) and ovariectomy groups (15 heads). They were fed low calcium diets for 4 weeks after experimental operation and 12 more weeks. The experimental group received a daily administration of P diet for 4 and 8 weeks after oophorectomy. Therefore, we measured levels of calcium, alkaline phophatase (ALP), phosphorous, trabecular density of tibia, ash weights in tibia and femur. The level of serum ALP of P diet was showed a significant decrease in comparison with sham group. Calcium and phosphorous were almost not changed between three groups. The weight of tibia and femur of P diet was increased in comparison with sham group in 8 week after oophorectomy. The trabecular bone density in ovariectomy group showed significant decrease in comparison with sham. Those in P diet-treated showed significant increase in comparison with sham after oophorectomy. Accordingly to the above results, effects of the P diet on the rat osteoporosis showed a efficiency in elevation of bone density by increasing bone weight by ovariectomy. So P diet can be used for preventing and curing of the postmenopausal osteoporosis, as for it's effects, continuous clinical study is needed.