In order to build the safety culture for nuclear power industry,tt is important to evaluate the safety culture scientifically.Considering the traits of safety culture in the nuclear power industry,24 safety culture assessment indexes are established from 4 aspects such as Safety consciousness,Safety attitude,Safety action and Safety actuality by using the SMART criteria.Safety culture star-class assessment criterion is presented and safety culture star-class assessment system is developed by using Visual Basic 6.0 and BP neural network.The system has a better generalization ability,and it can show exactly which phase the safety culture is in.Experimental results show that safety culture star-class assessment is practical and easy to perform.