By introducing the coke powder into the friction pair, the effects of load and temperature on the lubricity of coke powder at the frictional interface are studied. Before the test, the microcrystalline structures of coke powder at different temperatures are characterized by X-ray diffraction (XRD). After the test, the friction surfaces are observed by electron microscope and energy spectrum, the oxide compositions of friction surface are characterized by XRD, and the lubrication mechanism of coke powder is investigated. The results show that at RT (room temperature), as the load increases, the forming of the powder layer gradually deteriorates. When the load is 5 MPa, at a low temperature, the powder layer is thicker, and the coke powder exhibits better lubricity. In contrast, at a high temperature, affected by the temperature, the lubricity of coke powder declines, and the friction coefficient is higher.