To improve the generating precision of driving signal in multiple-input multiple-out (MIMO) linear random vibration test system, a new method called Cholesky decomposition(CD) filter based on white noise is proposed according to the matrix decomposition theory in view of the nonnegative definite Hermite characteristic of driving powr spectral density(PSD). The lower triangular matrix with particular frequency response transfer characteristics is constructed. A series of independent white noises are passed through the system, and the multiple stationary random signals with articipative coherence performance, phases and self-PSD are obtained. A two-input two-output simulation system based on a cantilever beam is established to verify the effectiveness of the proposed method. The mixed reference spectrum including board and narrow random signals is set and the results between the traditional time-frequency transformation method based on Fourier transform and the new method are compared. The results show that the new method has high accuracy in the self-spectrum and cross-spectrum, and can meet the technical requirements of engineering application, thus improving the effect of random vibration environment test control.