In recent years, the application of the finite element method to the identification and control problem has become more and more interesting, especially for systems with irregular boundaries. The present work proposes a combined mathematical model utilizing finite element discretization in terms of space elements and orthogonal function expansions of nodal time responses, instead of the conventional finite difference approximation for time derivatives. The present approach directly reduces partial differential equations to a set of recursive algebraic equations and thus saves analysis computation time. Based on this mathematical model, the identification of system parameters in distributed systems has been carried out utilizing the least-squares method. The identification procedure is straightforward, and—as shown by illustrative examples—the results of the present approach are excellent.