长江口入海航道７米挖槽开挖以后，洪季挖槽内出现１２米的浮泥层，引起了生产部门和研究机构的高度重视。本文介绍了长江口浮泥的一般情况，讨论了浮泥层变化的某些规律、探讨了在长江口测量浮泥层底板水深制作海图、充分利用浮泥层作为通航水深，在理论上和实践上都取得了一定的成绩。 After digging a 7-meter trench in the inlet channel of the Yangtze Estuary, a 12-m-thick floating mud layer appeared in the trench during the flood season, causing great attention to the production departments and research institutes. This paper introduces the general situation of floating mud at the mouth of the Yangtze River, discusses some regularities of the change of the mud layer, discusses how to measure the water depth of the floating mud floor at the mouth of the Yangtze River, makes full use of the floating mud layer as the navigable water depth, In practice have achieved some success.