According to the theory of matrix optics, axisymmetric paraxial optical system can be described by 2×2 matrix and it is necessary to get the accurate optical parameters and geometric location information of all components when determining the optical system matrix of optical system. A new method to determine optical matrix elements of system using digital holographic experiment is put forword, free from knowing the relevant parameters of the system element. Furthermore, experimental evidence of detection method is given. The experimental study show that the matrix elements can be obtained accurately with method, which has practical significance for applications of matrix optics.