Abstract: To identify distributed parameter systems with the aid of an orthogonal function series is a kind of effective method for identification. On the basis of a simple wavelet function basis? the Haar orthonormal basis, a method for system identification applied to distributed-parameter systems is presented in this paper. The identification accuracy is higher due to the application of a direct integration algorithm to the integral operation matrix. Also, the proposed method is more applicable in consideration of the affect of the initial and boundary conditions on the identification results.