Abstract: From the perspective of reducing the control time, based on the propagation mechanism of overload-dominated cascading failures, this paper develops a blocking control method against cascading failures, which takes into account economy and rapidity. First, the line overload protection model is used to quantify the line tripping time. The line with the minimum tripping time is tripped as the next fault link. Based on this, the prediction method for propagation paths of cascading failures is established considering the hidden failure of relay protections. Then, a blocking control model to minimize control cost and blocking time is presented, and the risk importance index of faulty links is defined to select the optimal position for applying the blocking control strategy. Finally, the IEEE 39-bus system and the IEEE 118-bus system are used as cases for simulation. The results show that the proposed model can ensure the rapidity of the implementation of the blocking control strategy while taking into account the economy, effectively preventing the spread of failures and reducing load loss.