The cluster analysis method to determine the water-masses in the shallow water area can overcome some difficulties which are met in using analysis method of the oceanic water-masses. According to the features of different sea area, this method applied in defining the marginal value and inspectoral value possesses great flexibility.The correlations of the modified water-masses in the shallow water area with the central fishing grounds are discussed in this paper.The results show that the bottom layer cold waters and surface layer waters of Donghai Sea and the coastal waters of continent are important factors effecting the fishery production in this area. Therefore, it is necessary to use this method in research and analysis of the Variation.