For coastal and estuarine morphdynamics, consolidation of fine sediment is of crucial importance for us to understand its influence on sediment dynamics process. Based on a new settling column and the DensiTune, three series of consolidation experiments are carried out, the difference between those series is the median grain size, all the sediment samples are collected originally from the Yangtze estuary. Two methods, the density method and the McLaughlin method, are employed to calculate the consolidation velocity. Experiments have shown that the flocculation becomes weaker when sediment size increases, and we find that the grain size is a significant impact for fine sediment consolidation. According to careful analysis and comparison, the consolidation velocity of fine sediment in the Yangtze estuary is in the range of 0.31×10-3~4.8×10-3 mm/s.