Soil vapor extraction (SVE) is known to be an effective process to remove the contaminants from the soils, which enhances the vaporization of organic compounds by using forced vapor flows or applying vacuum through soils. Experiments and calculations are carried out to investigate the effects of the organic contaminants, types of soils, and water contents on the removal efficiency with operating time. In the study, simulated soils include the glass bead which has no micropore, sand, and molecular sieve which has a large volume of micropores. As model organic pollutants, toluene, methyl ethyl ketone, and trichloroethylene are selected. Modelling is carried out considering Freundlich isotherm (S=KC^N) and pore diffusion model. Result shows that the rates of desorption of organic compounds from the soils are dependent on the concentration of organics residues in soils. At the initial stage, the N value approaches to one. However, this value decreases with the process of desorption process. In addition, when soils contain the water, the K value in the expression of Freundlich isotherm increases for the desorption process. It is also found that the K value increases when Henry's constant of organic compound decreases, the solubility increases, and the pore volume or surface area of simulated soil increases. The results could provide a basis for the design of SVE process.