Through laboratory experiments, the soil moisture infiltration characteristics a nd the distribution rule of soil moisture in wetting front are studied under the condition of different additives and proportions. Results show that the relatio nship between soil moisture diffusivity and soil water content can be better de scribed by an exponential function. The soil with a certain additive can prolong the time of high moisture in the arable layer. The treatment with 3% and 1% mai ze leaf can improve soil water content effectively. The results can provide an e ngineering method for large scale soil improvement. 