In order to further reduce the energy loss of induction motor under dynamic operation condition,a strategy of energy-saving control based on model of induction motor in full speed range was proposed. The strategy based on the loss model considering the effect of the leakage inductance establishes the mechanism relationship of controllable loss affected by the speed and the current. The region of speedSchange was divided when induction motor run in full speed range. The Kuhn-Tucker theorem was determined the strategy of optimal energy-saving control when the load fluctuated in the different regions with the speed change. In the field-weakening region,it allocates exciting current and torque current reasonably in the form of the diagram of current control track to improve the biggest output torque of asynchronous motor. Through simulation analysis,it is demonstrated that this strategy can be effectively improved efficiency of induction motor. It not only improve the biggest output torque in the field-weakening region,but also make the system achieve the best running state.