Chaotic masking communication program is the basic method and it is also easy to implement, however the required amplitude for the transmitted message is rather small. Therefore the transmitted message is sensitive to the channel noise, and then the decoding message has a lower accuracy. A method of chaotic synchronization based on the linear stability criterion is utilized, and a technical scheme of chaotic masking for secure communication is proposed. A nonlinear drive vector function of special chaotic state variable is constructed by a proper separation of the linear and nonlinear terms in a chaotic system. The transmitted message is injected into one element of the state vector. Thus the scheme increases the complexity of masking message and the decoding difficulty. Lorenz attractor and Chen attractor are used as an example to simulate the application of sinusoidal information transmitted by chaotic masking technique. The configuration of the Jacobi matrix is flexible and multiple choices. A simple and optimal chaotic masking scheme is given through comparative analysis. Numerical analysis shows that even if the amplitude of sine function information for transmission is quite large, there is no effect on the decoding accuracy of the information. The proposed scheme is effective.