Though speed effect and tension effect are keys to controlling thickness in producing aluminum foil, sort of their mathematical models, which will be widely used, can't be obtained theoretically at present. Based on the study of aluminum foil rolling in some factory, speed effect and tension effect of some 1850 aluminum foil mill are analyzed, and mathematical models which are about the relation between the exit thickness of aluminum foil and the speed change and the tension change, are developed according to the attained trial data. Those models are used to optimize the process of this mill.