A digital-twin modeling method for an automated testing pipeline for circuit breakers involves acquiring a three-dimensional digitalized model of each mechanical installation in the testing pipeline; modeling hierarchy according to an actual production process and motion states; performing mesh optimization on the resulting model; designing movements of each said mechanical installation, so as to obtain mechanical movement tracks of the models; combining actual movement logic and cooperative relationship among the movements to edit the mechanical movement tracks of the models; and introducing motion control, so as to conduct motion simulation in a digital-twin scene, thereby implementing virtual movements synchronous with movements of the actual testing pipeline. The method realizes centralized management of production data of the pipeline and realizes remote visualized operation, management and maintenance of the testing pipeline, thereby providing a basic platform for digitalized production of miniature circuit breakers.