Abstract: Objective To study the effect of astaxanthin osseous changes in D-galactose-induced rats.Methods To cause aging,Wistar r ats were injected with D-galactose for five months.They were randomly divided into four groups,in-cluding young control group,model group,astax anthin group and old control group,whose osseous routine parameters were tested and compared.Results Compared with young group,bone density,structural power parameters of bone,biological power parameters of bone,bone calcium,manganese,magnesium and the content of hydrox yproline in the model group,decreased and had statistical significance(P<0.01).How ever,the content of bone phosphorus,the activity of bone and serum ALP had statistical sig nificance and increased(P<0.01).Those changes of the model group were the same as those of the old control group,but those changes of astaxanthin group significantly differ ed from the model group.Conclusion The high does D-galactose can cause aging and osteoporsis at the same time,but astaxanthin can prevent osseous changes induced by D-galactose.