Objective This paper studied the surface texture, surface composition and corona characteristics of selected conductors of a certain region and analyzed the properties change law of the aged conductors. Methods Material composition and distribution on the surface of the conductors was analyzed by the field emission scanning electron microscope and discharge state was represented by the corona photon number under different applied voltages using ultraviolet imager. Results Non-metallic elements of the aging conductors were mainly O、C、S、Si and P, metallic elements were mainly Fe、Al、Ca、Na、Mg、K, and it was concerned with surrounding environment; the discharge photons of the aged conductors were more than the new ones under the same applied voltage. Conclusion Pollution particles and irregular surface structure was the discharge source of the corona under normal operating voltage; surface composition of the long-time running conductors differed with the different areas; irregularly surface of the conductors would cause the discharge inception voltage smaller than the new conductors, the operated years of the conductors had some effect to the surface state and the corona characteristics.