Abstract: In this paper, the symplectic multiresolution time domain method (S-MRTD) based on compactly supported scaling function is studied. In order to reduce the number of iterations in time steps, the optimized 3-stage 3-order symplectic integrator propagator is used to discretize in the temporal direction, and in the spatial direction, the time domain multi-resolution method with good dispersion characteristics is used to discretize. In this paper, the three-dimensional iterative formula of symplectic time domain multi-resolution scheme is given, which is applied to analysis of the characteristic parameters of waveguide structures. The numerical results show that compared with the conventional time domain multiresolution (MRTD), the S-MRTD method can still get accurate results when using coarse grids and high stability constants, which has the characteristics of less memory usage and higher computational efficiency.