The adsorption of extracellular DNA (a designed plasmid, pHTG) on the soil active particles and the influences of the minerals on the natural transformation of Bacillus subtilis were investigated with chemical adsorption and trace DNA detection analysis. The trace DNA was mixed with the three clay mineral solutions to clarify the adsorption characteristic of pHTG on permanent-charge soil active particles. The results showed that the adsorption of pHTG were dependent on the minerals. Different minerals had different adsorption. The maximum amount of pHTG adsorbed was in the order of goethite＞kaolinite＞montmorillonite. Minerals reduced the natural transformation. The transformation efficiency was decreased with the increase of mineral concentration. When mineral concentration increased from 0.0 mg/mL to 8.0 mg/mL, the transformation efficiency was reduced in two orders of magnitude. Montmorillonite significantly decreased the transformation, while goethite had the least influence.