This paper is the second part of a series reviews on the settling velocity of fine sediment in a tidal environment.Based on many domestic and foreign literatures,we discuss and compare the methods for determining the settling velocity and its formulation.In past relevant studies,a number of empirical or semi empirical formulas are proposed,each of which has its own applicable condition and limitation.Here the background of these methods and formulas are presented to remind us of making a reasonable choice during practical application.The conclusions are as follows:1)The D50 oriented formula can not take account in the basic feature of settling for fine sediment,so it is not recommended;2)The SSC oriented formula is site and case specified,the coefficients vary dramatically with different studies,one should be careful on the applicability;3)The Rouse formula can not distinguish the settling component of gravitational settling from the overall downward movement;4)Due to the strict physical meaning,the McLaughlin formula is recommended for formulating the settling velocity of fine sediment.