In mutual review of the contracting state based on IAEA international agreement in 2005, the Japanese government have received comment that total exposed dose of nuclear power plants in Japan has a different trend compared to other major countries. Analysis focused to the current state was executed based on the report of the annual dose to radiation workers, etc.. As a result, it is clearly that duration of plant operation is shorter than other countries. In other words, inspecting activities, duration of the activity and number of workers is more than other countries. However, annual average dose per radiation worker has been decreasing in recent years owing to continuance dose reduction measures. As a tendency in the near future, annual total dose will increase with large scale of maintenance such as modification for prolonged operation of the preceding plant in the future. On the other hands, there is expectation that new plants have one of the lowest dose is achieved by reflecting the finding of the preceding plant and it is thought that the annual dose per nuclear power plant decreases. This report includes the result of the analysis and measures and the prospect in the future.