The sakura shrimp (Sergia lucens Hansen) is a pelagic planktonic shrimp that is caughtcommercially in the Suruga Bay of Japan and the coastal waters off southwesternTaiwan. In Taiwan, the main fishing grounds of S. lucens are located in from betweennorth latitude 22 degree 6 minute and 22 degree 27 minute to east longitude 120 degree12 minute and 120 degree 39 minute. The area of fishing grounds, about 320 kmsquare, was only located in the isobath line of sea bottom between 100 m and 300 m indepth. The fishing season was during the period from November to May next year. Thesakura shrimp with thin shell, rich in calcium and directly consumed by people, was aprecious stock in the coastal waters of Taiwan. At the present time, however, few papershave been published for studying this shrimp. Therefore, to understand the ecology ofS. lucens and mechanism of fishing ground formation, the fishing data, sea conditionand S. lucens samples are collected monthly. We also want to study the initial usablestock size, the resource assessment and the determination of stock of S. lucens forestimating the optimum yield and establishing the sustainable management model.