Chaotic motion and chaos control of a permanent magnet synchronous motor (PMSM) are studied in this paper. The dynamics of chaotic PMSM with load vibration perturbation is presented and its complex dynamic characteristics are analyzed by using bifurcation diagrams, Lyapunov exponents, and phase portraits. Furthermore, an adaptive neural sliding mode control is addressed to suppress chaos oscillations for the PMSM. The neural network approximation is applied in the controller to emulate of the load perturbation. Simulation results show that the proposed control scheme can eliminate the chaos and make the system achieve stable states even with the existence of unknown load vibration disturbance.