Abstract: The U.S.Nuclear Powered Warships have safely operated for more than 50 years without experiencing any reactor accident or any release of radioactivity that hurt human health or had an adverse effect on marine life.Naval reactors have an outstanding record of over 151 million miles safely steamed on nuclear power,and they have amassed over 6500 reactor-years of safe operation.Based on general safety principles and safety requirements,safety regulation and safety technology of the US naval reactor plant,the paper studies the safety measures of the US Nuclear Powered ship reactor plant.