Abstract: In this work, a 2.5-dimensional discontinuous Galerkin time-domain(2.5D-DGTD) method with perfectly matched layer is proposed as a flexible tool to solve accurately electromagnetic problems in which media are homogeneous in one direction. Two numerical examples are simulated to demonstrate the advantages of the proposed method, which are the coupling between an electric dipole and optical fiber, and the analysis of dispersion characteristics of a photonic crystal fiber. The method is compare with the traditional 2.5-dimensional finite-difference time-domain method. The results show that the 2.5D-DGTD method is more realistic, especially for the simulation of curved shapes, where compared the calculation memory is reduced by 10.4%, the calculation accuracy differs by 0.011%, the calculation time is shortened, and the calculation efficiency is increased by 74.9%.