Ionic-strength and pH are two most important chemical factors affecting transport of Kaolinite colloids.A lysimeter experiment using a column of saturated quartz was carried out to determine effects of ionic intensity (0.001 5～0.03mol L^-1) and pH (5～9) on mobilization of Kaolinite colloids.Results show that deposition of Kaolinite colloids increased with rising ionic intensity and so did retardation of the transport of colloids.The deposition of Kaolinite colloids is the lowest in neutral environment (pH7.10) and the highest in acid porous media (pH4.98).