首先分析了杭州湾、长江口冬季余流和物质输运作用的观测特征，提出了几个值得继续研究的问题．然后，利用杭州湾、长江口三维联合模型，综合考虑径流、风应力、密度流、中国东部海域背景环流和M2，S2，K1，O1四个分潮的综合作用，模拟出了冬季的余流结构及其对物质的输运作用．在此基础上，针对所总结的几个问题，进一步作数值模拟，讨论余流和物质输运作用形成的机制．“,”First, some observational characteristics of residual current and mass transport in the Hangzhou Bayand the Changjiang Estuary in winter are analyzed. Then, the residual current and its effect on mass transport aresimulated with the 3-D joint model of the Hangzhou Bay and the Changjiang Estuary, in which the impacts of riverflow, wind, baroclinic pressure induced by temperature and salinity, current of the East China Sea and tide (includ-ing M2, S2, K1 and O1 ) are taken into account. Based on these studies there are also some simulations to analyze thedynamical mechanisms of the observational characteristics