The invention discloses a combined type high-voltage DC circuit breaker with a self-energizing ability, and a self-energizing strategy thereof. According to the combined type high-voltage DC circuit breaker and the self-energizing strategy thereof, a daily through-current branch of a traditional combined type high-voltage DC circuit breaker is improved, a load transfer switch is changed from the original mode of IGBT series connection to a mode of full-bridge submodule series connection, and the corresponding self-energizing strategy is designed, so that capacitors in submodules operate in an energized manner under normal working condition. The load transfer switch of the circuit breaker typology is energized by means of the capacitors of the submodules directly without the need of external power supply, the insurmountable insulation problem in engineering is avoided, and the application prospect of the circuit breaker in a high-voltage DC power grid can be improved.