Abstract: In order to reduce the loss caused by soil for agriculture and ecological environment deterioration, to guarantee the sustainable development of agriculture in Hunan and provide scientific basis for the ecological environment protection. A field experiment and laboratory analysis were performed to study acid characteristics in garden soil in the suburb of Changsha City. The results showed that: only applying chemical fertilizers could significantly reduce soil pH and promote soil acidification. Applying MgO and CaO treatments could effectively reduce the acid of surface soil, but the effect on the improvement of the bottom soil acid was not obvious. Exchangeable acid and pH value had an inverse relationship, and only at the lower acidity, exchangeable aluminum ions could be appeared in soil. Top soil CEC values were relatively stable, and soil CEC ranged from 8 to 10.75 cmol/kg with an average of 9.05 cmol/kg. The preserving-fertility and acid-base buffering capacity in the tested soil was weak.