The invention relates to an overcurrent protection method and a device for a hybrid high-voltage DC circuit breaker. The protection method comprises the following steps of: detecting a current changerate of a hybrid high-voltage DC circuit breaker side of a DC line and comparing the detected current change rate with a protection setting value; If the current change rate is greater than the protection set value, the hybrid HVDC circuit breaker is controlled to be disconnected to protect the HVDC line and power electronic equipment from overcurrent. According to the detected current change ratedi/dt, the invention predicts the fault occurrence trend, and before the fault current develops to a certain degree, the circuit breaker is switched on and off, which is not affected by the transmission line distance, transmission system parameters and the like, and has high reliability and sensitivity.