The chemistry composition of the high temperature oxidization under loads has been analyzed for the Cr5Mo alloy in this paper. The experimental research to the Fe, Cr and O elements have also been done. The difference between loads and no loads has been emphasized to the chemistry elements of the Cr5Mo alloy. The experimental results showed that the temperature couldn’t change the rate of the chemistry elements, but the loads could change them. The chemistry elements Fe ，Mo and Cr could change more obvious than other elements of the Cr5Mo alloy in this paper.