After the basic concepts，the basic principles and the main application methods and achievements of interdependent networks theory were briefly introduced，the multi-network characteristics in ship level repairing were explained，with the professional repairing networks，the repairing link networks and the management level networks as the case. The repairing networks，the equipment purchasing networks，the loading and moving networks and the technical guidance networks were respectively taken as the standard networks，whose interdependency between other networks was analyzed. In addition，the necessity of the study and the feasibility of the methods were verified by an example. This paper might provide methodological support for analyzing and finding weak links in the schedule management of ship level repairing，which means a lot to improving work intensity of ship level repairing and ensuring the ship level repairing finished on schedule.