This paper describes efficient iterative techniques for solving the large sparse symmetric linear systems that arise from application of finite difference approximations to self-adjoint elliptic equations. We use an incomplete factorization technique with the method of D'Yakonov type, generalized conjugate gradient and Chebyshev semi-iterative methods. We compare these methods with numerical examples. Bounds for the A-norm of the error vector of the Chebyshev semi-iterative method in terms of the spectral radius of the iteration matrix are derived. © 1990, Taylor & Francis Group, LLC. All rights reserved.