Based on the data of special investigation in waters of Dongwangsha,Hengsha,Tongsha,Nanhui and Fengxian(121°45’121°58’E,30°48’31°36’N), studies on capture size and yield in monitoring season of elvers of Japanese eel in the Yangtze River Estuary were carried out during 1997-2008,at the same time MSY was estimated.In the Yangtze River Estuary,the combined catch in February and March accounted for 64.53% to 94.10% of annual yield with an average of 79.32%. In the past years,peak of catch appeared the earliest on February 3 and the latest on March 15.In 1999,2000,2004 and 2006,shape of daily catch fluctuation showed two peaks with an interval of 36 days equally.Livability of elvers of Japanese eel rose by month from January to April,and the results showed that unit catch peaked in February,followed by in March,January and April.In all of the surveyed areas,livability of elvers catched in Tongsha station was higher than that in others,and so was unit catch in Nanhui station.Mean values of total length and body weight were (54.9 ± 3.4) mm and(92 ± 18) mg respectively.Values of two biological parameters increased gradually from January to April,and monthly increased ratio of total length was 3.10%, compared with 9.74% of body weight.In monitoring season during 1997-2008,permissive boats ranged from 954 to 4 713 units,with an average of 2 190 units.At the same time,annual yield ranged from 0.830 to 8.897 tons,with an average of 3.784 tons.MSY evaluated by Schaefer was 4.828 tons,and corresponding fishing effort were 2041 units.The results indicated that annual yield of elvers of Japanese eel in the Yangtze River Estuary increased significantly since 2003,but sharp fluctuation with a downward trend could also be found during 2003-2008.To achieve the sustainable utilization of resource of elvers of Japanese eel,this paper proposed that measures should be taken as soon as possible to put the lid on illegal fishing activities severely,arrange the numbers of fishing licenses dynamically,control the export proportion reasonably and shorten allowable fishing period to two months(February to March).