Abstract: The adsorption characteristics of 6 CWS dispersants on 14 coals surface were studied. The results show that most dispersants exhibit multilayer adsorption after achieving monomolecular layer saturated adsorption. The saturated adsorption amount of monolayer is mainly dependent on the coal rank, specific surface area of coal and the structure and property of dispersant. Under the same particle size distribution, either the higher the coal rank, the larger the adsorption amount of dispersant on coal surface; or the larger the specific surface of coal, the larger the adsorption amount. For different coals, the structure and property of dispersant will affect whether the coal rank or the specific surface of coal is the main factor to determine the adsorption of dispersant. The saturated adsorption amount for dispersant on unit surface area of coal increases with increasing coal rank and decreasing porosity of coal. When the dispersant is a length chain polymer, its hydrophilic and hydrophobic groups are linear schismatic distribution, resulting in a larger adsorption amount owing to the dispersant adsorbing on the coal particle surface by vertical form. When the hydrophilic and hydrophobic groups of dispersant are linear alternate distribution, leading to a smaller adsorption amount owing to the dispersant adsorbing on the coal particle surface by horizontal form.