Abstract: There exist various potential accident risks while the exploitation of nuclear energy has produced increasingly huge benefits for each state. Nuclear accidents can not only result in internal harms, but also produce transboundary damage. Compensation subject of nuclear accidents should primarily be the operator of nuclear installation, and the state just constitutes a complementary subject. However, since a state undertakes precaution and management responsibility on nuclear accidents, so a state should solely bear compensation for its fault when it fails to fulfill its responsibility.