Abstract: Ship deployment and repair activities should be managed in accordance with its own periodical repair structure throughout the life span of ship,however,for the fleetwide repair activities,it must be carried out under the guidance of the periodical repair structure of other ships in the fleet,that is to say,the repair should proceeds in concert with the other ship repair schedule,so as to expand the deployment period of fleet by obtaining optimal periodical repair structures of all ships.Quantitatively modeling the periodical structure for ship repair,a repair scheduling model was established to optimize the deployment capability of fleet by the use of genetic algorithm.The analyses of examples show that the deployment period of fleet will be expanded up to 110 months based on the optimal periodical repair structure,50 months longer than that without optimization.