Abstract: The cathodic protection by sacrificial anodes of couper alloy pipes in seawater environment were investigated by electrochemical test,galvanic corrosion test and corrosion simulation. The results showed that a proper potential gap existed between iron-based sacrificial anodes and copper alloy,indicating that iron-based anodes could have a better cathodic protection behavior and lower consumption rate than zinc-based anodes could. The cathodic protection properties of iron-based alloy were affected by the sizes of the pipes needing protection,and the effective area were about 10 times of the diameter.Resultsof the reseach presents significance in protecting the copper alloy pipes from corrosion and substantial engineering value in cathodic protection design for copper alloy pipes in seawater environment.