Abstract: According to the performance requirements for materials used in the seawater pipeline system on ships,the antifouling,forming,welding and anticorrosive properties of BFe10-1-1 alloy and HDR dual-phase stainless steel are comprehensively analyzed.The results indicate that BFe10-1-1 alloy remains to be the optimum material used in the seawater pipeline system on ships.Though it is good in anti corrosion, HDR dual-phase stainless steel is unfit for the seawater pipeline system on ships for its poor antifouling property.