Abstract:The base bearing seat,which is the key component of the operation for a miter gate,is not only the carrier of load transfer,but also the transition joint between bottom water seal and side inflexible water seal.It has aroused extensive attention for the reason of the characteristics such as difficult manufacturing and complicated installation and so on.In this paper,based on correlative theory, three kinds of design methods:involute method, multi-segment arc method and single arc method,which are uesed frequently when designing a bearing seat,are demonstrated one by one. Finally,combining with the manufacturing process and engineering practice,the advantages and disadvantages of three design methods are compared and analyzed,the optimal design method is recommended and also offering the reference and basis theoretical for the design of a base bearing seat of a ship lock.