The invention relates to a fault diagnosis and evaluation method for a battery energy-storage power station. The method comprises: on the basis of state information of a battery, a converter device, power distribution equipment, and a communication system, a battery fault diagnosis and evaluation model, a converter device fault diagnosis and evaluation model, a power distribution equipment fault diagnosis and evaluation model, and a communication system battery fault diagnosis and evaluation model are constructed respectively; fault diagnoses and evaluation are carried out on the battery, the converter device, the power distribution equipment, and the communication system in the battery energy-storage power station based on the battery fault diagnosis and evaluation model, the converter device fault diagnosis and evaluation model, the power distribution equipment fault diagnosis and evaluation model, and the communication system battery fault diagnosis and evaluation model; and a fault diagnosis and evaluation model of the battery energy-storage power station is established to carry out fault diagnoses and evaluation on the battery energy-storage power station. According to the method, on the basis of characteristics of the battery energy-storage power station, fault diagnoses of the battery energy-storage power station can be realized rapidly by means of combination of a distributed diagnosis and a centralized diagnosis and a fault point can be found out.