Abstract: In order to study the influence of the number and layout of sacrificial anodes on the protection performance of sewage storage tanks, the distribution of cathodic protection potentials when the number of anodes is 0, 1, 12, 16, 20 were respectively characterized. The results show that the Al-Zn-In series aluminum alloy anode material has a more even second phase distribution and dissolution; the corrosion potential of the storage tank in the sewage without anode protection is about -0.482 V; when the number of anodes is 20, the potential is about -1.02 V, which can protect the entire storage tank from corrosion; the storage tank protection potential could be -0.960 V and -0.786 V respectively when 16 and 12 anodes are applied and when the number of anodes is 14, the anode protection effect can reach the standard requirements; if any one of the anodes has a false weld, etc., the number of anodes must be not less than 16; when the mud layer thickens and the water level drops in the tank, the anode will lose its protective effect; the welding between anode and tank plate should be firm, and the welding slag should be removed after welding; improper anode welding height is improper, because false connections and excessive consumption of individual anodes may lead to poor protection of some areas of the tank.