In view of the large volume of concrete for the head of high-head ship lock and the arrangement of various structures such as buried parts,holes and corridors,the severe changes of temperature stress and structure which are liable to cause concrete cracking,and combining with the construction of Zhuzhou second-line ship lock head,we carry out a research on key technologies such as the mix proportion design,temperature control measures,as well as the retarded mortar and mass concrete pouring.Adopting the method of three mixing and laying retarded mortar between layers,and combining with appropriate temperature control measures,no temperature cracks or interlayer seepage occur at the lock head.Based on the implementation of this project,we summarize the technical achievements of preventing temperature cracks and interlayer cracks in mass concrete construction of lock head,which may serve as reference for similar ship lock construction.