The invention discloses an EXata-based simulation method for an SDH optical transmission network in a power system. The method comprises the following steps: firstly dividing the actual SDH network cell equipment into multiple logical function modules according to logical functions, carrying out modeling on the logical function modules on a simulation platform, so as to construct virtual models for the logical function modules, and building virtual SDH network cell equipment according to the virtual models for the logical function modules; then building a virtual topological structure of the actual SDH optical transmission network; then according to the logical function required to be realized by a business type of the actual SDH optical transmission network, finding the virtual SDH network cell equipment with the logical function, and applying the virtual SDH network cell equipment to the virtual topological structure; and finally carrying out simulation run on the virtual topologicalstructure on the simulation platform. The simulation method disclosed by the invention is convenient for configuration of simulation parameters and high in expandability and can effectively realize simulation of the business type of the SDH optical transmission network, and simulation efficiency is relatively high.