【Objective】 It is of great scientific significance to study physical, chemical and biological processes of the migration of colloidal particles in saturated porous media. Therefore, it is essential to determine factors affecting the migration and deposition of colloidal particles in saturated porous media. 【Method】 An in-lab quartz sand column experiment was conducted to study migration behavior of colloidal particles in the sand column. The colloidal particles, were poured into saturated porous media with water solution of a set water head. The experiment was designed to have three levels of particle size of the colloidal particles, three levels of concentration of the colloidal solution and three levels of particle size of the quartz sand in the column.【Result】 Results show that K/K₀ of the media was reduced to an extent that was positively related to concentration and particle size of the colloidal particles in columns treated with colloidal particles the same in particle size. The smaller the size of the colloidal particles with the same concentration, the larger theK/K₀ of the overall column and the AB segment (surface layer) at the end of the experiment, and the smaller the K/K₀ of the lower EG segment (bottom layer), indicating that large particles were more likely to deposit in the surface layer, while small particles were to move to the bottom. As a whole, the particle size effect was not as noticeable as the effect of change in particle concentration. When the colloidal particles migrated through the porous media different in particle size, K/K₀ of each segment of the porous media large in particle size was significantly lower, while it was only low in the surface layer of the column of sands small in particle size. Regression analysis of temporal variation of the overall relative permeability coefficient with other factors shows a quadratic relationship between the two with R2 being greater than 0.92 except in a few cases, which indicates good correlations. However, the correlation was not significant when the porous media were small in particle size. Analysis of velocity variation indicates that the higher the colloidal particles in concentration and particle size and the porous medium in particle size, the faster the decline of flow rate. Comparison between columns treated with colloidal particles different in concentration and in different particle, separately shows that large particles concentrated mostly in the upper part of the sand column, while small particles did in the lower part, which corresponded to the change of the medium in permeability. Qualitative characterization of the columns with a scanning electron microscope displays significant deposition of colloidal particles on the surface of the porous media after the experiment, which further demonstrates that colloidal particles could clog pores of the porous media, thus affecting their permeability. Secondly, the deposition of colloidal particles in the porous media increased K/K₀ under certain conditions, which was related to concentration C₀of the input and diameter ratio d_p /D_p ( d_p stands for colloidal particle size, and D_p for arithmetic average particle size of the quartz sand) of the particles. Phenomena of rising local permeability coefficient would appear when d_p /D_p was higher than 0.018 and C₀was lower than 0.5 g•L^-1. 【Conclusion】 Generally speaking，the colloidal particles migrating in porous media may clog the pores of the media physically, and hence reduce their permeability. Particle size and concentration of the colloidal particles tested and particle size of the porous media are main factors affecting migration and deposition of the colloidal particles in saturated porous media.