Station backup protection based on the current fusion reliable factor is proposed for easy access to all the information of local protection action. First, this paper updates setting values based on the principle of adaptive current protection, collects the action information of current protection and calculates support degree that protection against each component based on effective protection range. Then, it regards the support degree as the right of protection and builds fusion reliable function and fusion reliable expected function of station protection. Finally, faulty component is identified according to their specific value, i.e. fusion reliable factor. The results show that the faulty component can be identified correctly and quickly, and information missing and error situation can be coped with. This scheme of substation protection has good adaptability and fault tolerance.