For electric propulsionSship power system, faultSmonitoringSalarm devices with system were researched and developed under the FieldbusSand industrialSEthernetStechnology as foundation, and using the electric parameterSmeasuring instrument,Spower quality monitoring instrument,SanalogSSpointerSgauge,SPLC,Stouch screen, industrial computerSas core equipment. The implementation of hardware devices, using the Modbus field bus centralized monitoring system structure design technology and equipment configuration method. Implementation of software, using the fault alarm logical judgment, centralized monitoring and human-computer interface design, fault information processing and technology of message transmission between devices. The monitoring system is composed by several devices of power generation, power transmission and propulsion load. The functions of the devicesSsatisfied the applying requirements in shipSpower systemSlaboratory. It is indicated that improving the safety and reliabilitySof power system.