Abstract: [OBJECTIVE] Effects of water-keeping from super absorbent polymer in Nanfeng mandarin orchard were studied in order to provide a theoretical basis for high-yield and good-quality of Nanfeng mandarin. [METHOD]The research took ‘Yangxiao 26’as experimental material to study the effect of the RT-3005KM super absorbent polymer on soil moisture content of Nanfeng mandarin. [RESULTS] The results indicated that the soil moisture content in 0-20 cm soil layer was not distinct with the amount of super absorbent polymer. Soil moisture content heightened with the super absorbent polymer increasing in 20-40cm soil layer. Soil moisture content decreased with the super absorbent polymer increasing in 40-60cm and 60-80cm soil layer, respectively. The soil moisture content with the same treatment in 40-60cm soil layer was higher than that in 60-80cm after rainfall. It seemed that there was a peak of water absorption treated with super absorbent polymer in 40-60cm soil layer. [CONCLUSION] On the whole, the super absorbent polymer could increase the soil moisture content of Nanfeng mandarin.