Safety assessment of bridge crane metal structure is widely needed. A general bridge safety assessment model of metal structure based on BP neural network is established. BP neural network is suitable for the problem that is not fully known and the adaptability of the dynamic system, and can facilitate the assignment and statistics of the safety evaluation system. Matlab7.0 software is used for the network training process. Through the training, samples to be tested were verified for the feasibility of the security model. The security model based on BP neural network for the general overhead traveling crane structure could provide a safety assessment and evaluation methods.