Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 duringJune of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimensional non-linear diagnostic, semidiagnostic models and prognostic in the a coordinate. The computed results show that the density and velocity fields and so on have been adjusted when time is about 3 days, namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed region, the Huanghai coastal current flows southeastward, and then it flows out the computed region south of Cheju Island. In the west side of the southern part of the computed region, there is other current, which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to the northeast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Island , and it has characteristics of high density and low temperature. There is an offshore branch of Taiwan Warm Current i Based on the wind and hydrographic data obtained by R / V Xiangyanghong 14 during June of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimensional non-linear diagnostic, semidiagnostic models and prognostic in the coordinate. The computed results show that the density and velocity fields and so on have been adjusted when time is about 3 days, namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed region, the Huanghai coastal current flows southeastward, and then it flows out the computed region south of Cheju Island. In the west side of the southern part of the computed region, there is other current, which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to the northeast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Island, and it has characteristics of high density and low temperature. There is an offshore branch of Tai wan Warm Current i