The utility model discloses a state evaluation system of extra -high voltage arrester, include: the electrification of gathering the quantity of state of extra -high voltage arrester detects data, on -line measuring data and stops the collection module of electric test data, the data of gathering according to collection module with predetermine the quantity of state standards of grading, the grade module of grading is carried out each unit status of arrester, according to grading of the module of grading, assess the unit status of each unit status result of arrester and assess the module, according to each the unit status result and the predetermined arrester evaluation criterion of arrester, assess the global state of arrester global state result and assess the module. Can go on accurately more appraising effectively to special high -tension apparatus state, detect and provide the basis for special high voltage electric power equip ment such as extra -high voltage arrester carry out corresponding.