Objective To investigate the mechanism of icariin in treating osteoporosis of ovariectomized with gene chips technology.Method A total of 20 female SD rats were randomly divided into model group and treatment group,10 rats in each group.After ovariectomized to make model,treatment group was given icariin [aqueous phase 0.4 mL/(100 g.d),oil phase 0.6 mL/(100 g.d)],model group was given the same volume water and vegetable oil once per day for 13 weeks.Gene chips of RatRef-12-v15590097019 were used to investigate the gene expression profile of osteoporosis rats,and the different expressed genes were analyzed with Gene Ontology.Results A total of 532 significant differentially expressed genes related were detected.Among them,175 genes were up-regulated,357 genes were down-regulated.Conclusion Many genes differential expression are related with icariin in treating osteoporosis of ovariectomized rats.