To observe the effects of exposure of rat ovary to radiation or OVX on the expression of TGF−β,1, and COLI in the rat bone. The mRNA levels of TGF−β,1, and COLI in rat tibiae were measured with RT−PCR after the rat ovaries were irradiated by 50Gy of ,137,Cs γ−rays or OVX. For both the radiation group and the OVX group, the COLI mRNA level in the rat bone increased, whereas the TGF−β,1, decreased. Irradiation of ovary and OVX affect the expression of COLI and TGF−β,1, mrna in bone probably in a similar way which is related to estrogen decrease.