Abstract: A tracking synchronization control theorem of the simplified Lorenz system is deduced on the basis of the Lyapunov stability theory. We demonstrate that the system can, in theory, track any differentiable reference signals by employing this tracking controller. Using the controller, we investigate the tracking control issues of the simplified Lorenz system by tracking the direct current signal, sine signal, and hyperchaotic signal. The relation between the synchronization performance and the control parameters is discussed, and we demonstrate that a larger control parameter can reduce the synchronization setup time. Simulation results show the effectiveness and feasibility of the method, which provides a new synchronization scheme for the simplified Lorenz chaotic system to achieve chaotic secure communication.