Abstract:[Objective] The temporal and spatial distribution characteristics of deep soil water leakage and infiltration under saturated conditions in Otindag sandy land were analyzed in order to provide a theoretical basis for the evaluation of the sandy land water cycle, water balance, and water resources. [Methods] Deep soil leakage in Otindag sandy land semi-fixed caragana microphylla (vegetation coverage 20%~30%) and fixed deep seep of Caragana microphylla (vegetation coverage 40%~50%) below 200 cm was continuously monitored by a recording apparatus. [Results] In the semi-arid, low-rainfall area of Otindag sandy land, the characteristics of deep soil water leakage in different types of sandy land were consistent with the characteristics of rainfall, but the spatiotemporal distribution of leakage was different. The leakage was largest and the infiltration rate was fastest under saturated conditions, while the duration was longest in the mobile sandy land. There was a significant correlation between deep leakage and monthly rainfall in the mobile sandy land (p<0.05), and the fixed sand had no correlation in time and there was no obvious concentrated recharge period of seepage. [Conclusion] The vegetation in the semi-fixed and fixed sandy land affected deep leakage, and the higher the vegetation coverage, the greater the impact. The mobile sandy land can store more water and replenish underground water.