DC circuit breaker is the key equipment for the safe operation and protection of DC distribution network. In this paper, the application of DC circuit breaker in low voltage DC distribution system is investigated, a kind of all-solid-state DC circuit breaker prototype is developed. Firstly, taking Shenzhen DC dynamic simulation platform system as an example, the parameter requirements of typical low-voltage DC distribution system for the circuit breaker is analyzed. Secondly, the function and installation position of the DC circuit breaker in the protection system of the dynamic simulation platform are determined. At the same time, based on the requirements of DC distribution system for the main parameters of DC circuit breaker, the all-solid-state switch topology is selected for the DC circuit breaker, and on this basis, the absorption branch and the communication module are designed, and the software operating process in response to main control system of the DC circuit breaker is established. Finally, a prototype of ±380 V low voltage distribution DC circuit breaker with practical value is developed, and several related tests are carried out to verify the correctness of the circuit breaker design and protection scheme.