In order to implement the locomotive economize on energy.The system used P87C591 as control unit,CF card as data storage media.Predictive control is used in the control system of energy-saving operational locomotive.By establishing the predictive mode of locomotive energy-saving speed,we can predict energy-saving speed-distance curve,and then guide drivers to operate the locomotive in energy-saving ways, achieve energy-saving operation of the locomotive economically and reliably.