The durability of bridge structure is a key question of safety using during the full life-span of the long-span bridge over sea under the influence of atrocious surroundings of the sea.By analyzing the primary factors which influence the durability of the bridge over sea under the oceanic surroundings,the main approach and technical countermeasures which are in purpose of improving the structure durability are presented.Specifically,the design and construction technology countermeasures for the durability of Donghai Bridge's main concrete structures,steel structures and steel pipe piles are also summarized.And it's proved that the countermeasures are effective by testing results and using performance.