Abstract: In order to satisfy the development of UHV DC transmission line live working, based on the characteristics of UHV DC transmission line in Chongqing which only has the characteristics of three kinds of insulator, and on the basis of 500 kV live working train of thought, the design of live working tools is studied according to the material and combination forms of the insulators. The tool-base is established for the live working of UHV DC transmission line in Chongqing, which has important practical significance.