This paper deals with adaptive nonlinear identification and trajectory tracking problem via dynamic multilayer neural network with different time scales. By means of a Lyapunov-like analysis, we determine stability conditions for the on-line identification. Then, a sliding mode controller is designed for trajectory tracking with consideration of the modeling error and disturbance. The main contributions of the paper lie in the following aspects. First, we extend our prior identification results of single-layer dynamic neural networks with multi-time scales to those of multilayer case. Second, the e-modification in standard use in adaptive control is introduced in the on-line update laws to guarantee bounded weights and bounded identification errors. Third, the potential singularity problem in controller design is solved by using new update laws for the NN weights so that the control signal is guaranteed bounded. The stability of proposed controller is proved by using Lyapunov function. Simulation results demonstrate the effectiveness of the proposed algorithm. that a gradient descent algorithm for weight adjustment was stable and robust to any bounded uncertainties, including the optimal network approximation error [6]. All these researches are focused on the stability property analysis, such as the conditions that the system should satisfy to achieve global asymptotic stability, exponential stability, input-to-state stability, and short-term memory or long-term memory behavior of the neural networks. The research on identification and control for nonlinear systems by using dynamic multi-time scales neural networks is rare.Adaptive neural networks control is classified into two kinds of structure: indirect and direct adaptive control. In direct adaptive control, the parameters of the controller are changed directly without determining the characteristics of the process and its disturbance first [7,8,[14][15][16][17][18]. In indirect adaptive control, the parameters of controller are designed on the basis of the process model and possibly the disturbance model, which are determined first [9,10,[19][20][21][22][23][24][25]. In this paper, we focus on developing the indirect adaptive neural network controller for the nonlinear systems. So, the nonlinear system identification process turns out to be one of the central parts in constructing successful tracking controllers.System identification using neural networks has been investigated by many researchers. For instance, in [26], a multilayer feed forward neural network is utilized to identify the moving-average model of an induction motor. In [27], a robust identification method is proposed for nonlinear systems with unknown driving noise. Abdollahi et al. proposed a stable identification approach for multivariable nonlinear system based on nonlinear-in-parameters neural network in [28]. Neural networks are also utilized for modeling and identification of nonlinear dynamics for freeway traffic in [29]. Nevertheless, most researches performed before are based on feed ...