The utility model discloses a lightweight arrester installation base assembly, including be used for with the base assembly be fixed in the pole the fixed loop, with fixed loop fixed connection's support arm and fixed set up in the roof on the top of support arm, be provided with the mounting hole that is used for installing the arrester on the roof, mutually support through fixed loop and support arm, the bottom plate that adopts roof and arrester is with detachable mode fixed connection, can effectively alleviate the quality of installation base assembly, and bad news consuming time power improves work efficiency when avoiding the staff to install, guarantees the mounting structure intensity of installation base assembly simultaneously, stable and firm fixed arrester, and simple structure, simple to operate, low cost does benefit to the popularization.