Abstract: The Zeta potential of dispersion system forming by 10 dispersants with 14 coals was determined. The effect of dispersant on the interface electrochemical property of coal particles was studied. The higher the coal rank and the more the dissolved highvalence cations from coal, the lower the Zeta potential of dispersantmodified coal particle. The more the amount of hydrophilic groups and the charge of the anionic dispersant, the higher the Zeta potential of dispersantmodified coal particle. The nonionic dispersant leads to a decrease in the Zeta potential of dispersantmodified coal particle. In general, the Zeta potential of anionic dispersantmodified coal reflects its hydrophilicity. The maximum moisture content for most of dispersantmodified coal particles increases with increasing Zeta potentials. An experiential slurryability model including natural and dispersantmodified hydrophilicity of coal particle (Mad,ΔMHC), the Zeta potential of dispersantmodified coal particle (ζ) and the adsorption amount of dispersant on unit surface area of coal (Гs ) has been set up. It can be expressed as following: CFV = 76.621.896Mad 3.430△MHC+0.489Γs·ζ. The calculated value from this formula is approximate to the experimental result.