Abstract: The tribological behaviors of three grades of graphite, Lanzhou graphite,Shanghai Sangao graphite and IG--11, are investigated by the normal friction testerSRV. And the friction surfaces are analyzed by a scanning electron microscope. The ex-perimental environments are selected as helium and air. The results show that the fric-tion behaviors are different in different gas environments with the same load for allgraphite. At the large sliding velocities, the order of friction coefficient is Lanzhougraphite>Shanghai Sangao graphite>IG--11 in air, and in helium the order is ShanghaiSangao graphite>IG--11> Lanzhou graphite.