Abstract: The studies on reproductive biology and resource present of tapertail anchovy in the estuaries of Yangtze River in the recent years were carried on.The result showed that the average total length and body weight of the catching during the spawning period were 16.14?.70cm and 13.93?.21g,respectively.The total length was related to the power function of the body weight:W= 0.0034L2.8891,R2=0.9034.The diameter of matured egg was 0.67?.08mm;the absolute fecundity was 14190?703 eggs/fish,and the relative fecundity was 1073?75 eggs/g body weight.The absolute fecundity of the fish in spawning season had liner relationship with the total length and body weight. The total catching of tapertail anchovy in the estuaries of the Yangtze River varied around 1164 tons during 1997-1999,and the catching did not increase with the fishing effort.The abundance of the fish maintained between 20 and 30 tons at the end of the fishing season.Compared with previous years,the total catching declined significantly.The authors held that over fishing,deterioration of water environment and damage to the natural spawning ground were the main reasons,which caused the resources of tapertail anchovy to decline.