Hasi joint station uses the cathodic protection mode，combining the impressed current and anticorrosive layer. But at early stage，the protection efficiency is only 60%. To reduce the buried pipeline corrosion perforation, guarantee the safe operation of the equipment, the Hasi joint station has experienced three times of reconstruction and renovation. Aiming at the problems existing in the initial design, construction and maintenance of the cathodic protection system, the cathodic protection system has also undergone several times of expansion and maintenance, with which the effective protection efficiency increased to more than 95%. In this paper, from the effective practical measures for cathodic protection system, the implemented later expansion for cathodic protection station system and relevant solutions can provide reference to related personnel engaging in cathodic protection system design, construction and management.