The invention relates to a line failure recovery method of a direct-current power grid, and specifically provides three failure recovery methods respectively applicable to a half-bridge type main wiring mode with a convertor station connected with one direct-current line only, a full-bridge type main wiring mode with a convertor station connected with one direct-current line only and a convertor station connected with a plurality of direct-current lines. When the direct-current power grid is in failure, a direct-current line protection quickly identifies to generate an actuating signal and protects the actuating signal to perform reasonable and flexible coordination and cooperation through a current converter control system, a direct-current breaker and an alternating current breaker in combination with the main wiring mode of the converter and various operating conditions of the running status, so as to realize the quick recovery of a direct-current power grid system, and therefore reliability and availability ratio of the direct-current power grid system are ensured. A specific feasible technical scheme is provided for direct-current power grid project in planning, a targeted quick recovery solution is provided for the various operating conditions in operation, and the reliability and the availability ratio of the direct-current power grid system are ensured.