Abstract: It was analyzed that rolling oil stains form on the surface of an aluminum foil when the aluminum foil was annealed after roUing. The curves of thermal gravity and differential thermal analysis of rolling oil and additive were determined by means of a differential thermal analyzer. The results indicate that rolling oil has two phase changes with the increase of temperature. At first, rolling oil is volatilized in a large scale, and then oxidation occurs. The oxidation process is the main reason for the stains forming on aluminum surface, which theoretically reveal the effect of the thermal properties of rolling oil on the annealing surface.