Abstract: The research on robustness indicators is mainly focused on single network, but less on interdependent networks. This paper explores some commonly used robustness indicators. Aiming at the cascading failure of interdependent networks, a new robustness indicator based on the largest-component relative efficiency is proposed. With the simulation for rationality verification, the results show that the indicator proposed in this paper is more accurate to measure the robustness variations of the interdependent networks in the cascading failure process than those are commonly used at present, and it can be applied to simulation-based robustness analysis for large-scale interdependent networks.