In the soil environment，through analyzing the numerical solutions of pollutant migration, the time-space law of the transmission of organic pollutants in soil can be mastered, which has both theoretical and practical significance. The general mathematical model of the migration of volatile pollutant in soil was established; and typical models of pollution sources emission were calculated, and the influence of various parameters in model on calculation results were compared, such as diffusion, convection, adsorption and degradation parameters; finally a correlation analysis and discussion was made on calculation results of the pollutant concentration distribution. The calculation results show that the convection is the main reason causing pollutants migration, and the influence of volatility to migration process cannot be ignored. It provides the scientific basis and approach for the pollution forecasting and prevention.