Abstract: Through domain decomposition method, the method of lines combined with the finite-difference method is used to calculate the capacitance and inductance matrices of the multilayered multiconductor interconnections. The subregion with pure dielectric layers is analyzed by method of lines, while the subregion with conductors is analyzed by finite-difference method to take advantage fully the superiorities of these two methods. Numerical results show that the method in this paper is efficient, and the computing time is unrelated to the thickness of the pure dielectric layers.