For the control problem of a nonlinear uncertain system, a disturbance observation method and an elastic tracking control method are proposed based on the elastic energy function. The elastic energy function is applied to design the disturbance observer, virtual tracking instruction and elastic tracking controller, respectively, as the core technology. The prominent advantage of the proposed control method is only according to the error to eliminate the error, does not involve the differential operators of the error, and the controller gain parameters are determined completely by the integral step. Theory research show that the proposed elastic tracking control method not only guarantees the stability of various sub-controller theoretically, and effectively solves the control problem of higher-order SISO nonlinear uncertain systems, but also effectively avoids the differential explosion problem of the back stepping control method. In addition, each sub-controller has only one gain parameter which can be tunned by the integral step, so the controller has simple structure and small calculation. Simulation results show that the proposed elastic tracking control method not only has fast response speed, high control precision and strong ability to resist disturbance, but also is not dependent on the controlled object model, therefore has wide application prospect in the field of nonlinear uncertain systems control.