A fast fault recovery method for a flexible DC distribution network of an energy storage built-in converter is disclosed. The invention relates to a power system, especially to a fast fault recovery method for a flexible DC distribution network of an energy storage built-in converter. The invention provides a fast fault recovery method for a flexible DC distribution network of an energy storage built-in converter, that realizes fast fault recovery, fast recovery of a distribution network under bipolar short circuit faults and uninterrupted power supply during the fault removal period by a separate excitation mode through the coordination and cooperation between the converter and energy storage. On one hand, power is provided for important loads to ensure uninterrupted power supply during the fault removal; on the other hand, the capacitor voltage of a sub-module during the locking period is adjusted to reach the rated value during normal operation before unlocking, so as to reduce thevoltage fluctuation when the converter is unlocked again and shorten the restart time of the converter. Such a coordinated control strategy of the system can further ensure the improvement of the reliability of the entire distribution network system.