The invention provides a defense method for commutation failures of direct-current transmission based on a current limiting method. The method comprises the following steps: I, according to an output signal of failure detection, detecting the failure type of a commutation bus of a direct-current transmission system; II, by using the current limiting method, reducing a direct-current instruction and continuing for 60-100 ms; III, judging whether a failure is eliminated and a turn-off angle of the direct-current transmission system is restored; and IV, determining the direct-current instruction according to a judgment result until the failure is eliminated, and restoring the direct-current instruction. According to the method, adverse effects such as increasing a direct-current, increasing a power factor angle of the direct-current transmission system, and the like caused by advanced triggering are avoided, and a timely and effective response is made to an alternating-current system failure, so that the required commutation area of a thyristor is reduced, thereby facilitating that the direct-current transmission system is prevented from having commutation failures.