Column leaching tests were performed to probe the effect of simulated acid rain at different pH values on the acidification of grey-brown purplish soil from the Three Gorges Reservoir Region. The results indicated that the lower the acid rain pH value the more serious the acidification of the soil; the electric conductance of the solution leaching through different soil layers increased at first, then decreased, while the pH value of leachate changed reversely. In general, the higher the pH value and CEC content of the soil were, the greater the electric conductivity of the leachate was. The releasing amount of base ions in four types of typical soils increased with increasing rain acidity, while the leaching amount of aluminium in four types of typical soils increased with the decline of acid rain pH. Changes in the physical and chemical properties of respective soil layers to different degrees were detected after the addition of simulated acid rain of different pH values.