In this paper, a secure communication scheme is proposed using uncertain delayed chaotic system synchronization and disturbance observers. The disturbance observer is presented using radical basis function neural network (RBFNN). The parameter updated law of the RBFNN is given to approximate the system compound disturbance. The synchronization control scheme based on the designed disturbance observer is developed to synchronize two chaotic systems. When synchronization is achieved, the transmitter signal can be recovered from chaotic signal. Finally, an example is presented to illustrate the effectiveness of the proposed scheme.