The most basic and important function of DC circuit breaker is to break the short circuit current in time under the condition of short circuit fault. In order to effectively evaluate the breaking capacity of DC circuit breaker, it is necessary to simulate the harshest short-circuit current breaking condition in practical project. A topology structure of an equivalent breaking test device is presented based on the characteristics of hybrid DC circuit breaker. The topology composition, operation principle, stress analysis of key components, and calculation method of electrical parameters are also discussed. The research results can be used as the theoretical basis for the development of test equipment platform and the related work of DC circuit breaker breaking test.