Abstract: The finite-difference frequency-domain method with multifrontal algorithm is presented for two-dimensional cylinder scattering problems. The Mur's absorbing boundary conditions (ABCs) of the second order and the ABCs based on the concept of field average are applied at the terminating boundary mesh nodes. As the verification example, the scattering by an infinite cylinder of the perfect electric conductor is analyzed. CPU time is greatly reduced by using multifrontal method to solve the finite-difference equations. Numerical results demonstrate its accuracy and efficiency.