Owing to the high shipboard’s survivability and power supply reliability, the loop power distribution systems has been increasingly used in the large shipboard power systems. However, the conventional protection has a longer tripping time for the relay near to source, so that it can not clear the fault. This paper presents two methods of non-communication protection according to the characteristics of shipboard loop power distribution systems. In the methods, the changing of current through the local relay is adopted when the fault occurs and the remote breaker of the line is tripped. The two methods respectively use the time coordinations and the current ratio criterion of the accelerated overcurrent protections to determine the fault zone, and then accelerated trip of the local break. The simulation results of the Matlab/Simulink verify the reliability and the speed.