Aiming to the errors which were induced when wavefront was simulated with Zernike polynomials on the discrete points,a set of orthogonal polynomials expressed on a discrete point to simulate turbulent wavefront was proposed. According to the turbulence statistics theory,the turbulent wavefront expressed by Malacara polynomials was constructed with Gram-Schmidt orthogonalization. Compared with the method directly using Zernike polynomials,the results show that the method introduced in the paper is more accurate under the same conditions.