[Objective] Estimating the dynamic changes of groundwater resource changes and identifying possible safety measures, we aim to provide decision basis of managing available water resources and maintaining the ecological security of oasis.[Methods] Firstly, the total water demand of Cele Oasis was analyzed, and then the deficiency of water in oasis was calculated according to monitoring data on river and groundwater dynamics. Finally, the dynamic changes in groundwater level were analyzed using long-term monitoring data of groundwater.[Results] Results revealed that when considering the ecological water use, the average annual water gap in the Cele Oasis was 5.20×10⁶~1.15×10⁷ m³. On average, the annual decline in groundwater depth was varying from 0.27 m to 0.60 m due to continuous use of groundwater in Cele Oasis. During high flow years, the groundwater recharge was relatively abundant that did not make any obvious change in average depth of groundwater level except in its spatial distribution. During 2008-2014, the groundwater average depth showed more substantial fluctuations, but it basically maintained at the level of 21 m depth.[Conclusion] The change in groundwater depth in Cele Oasis is within safe range. But, in order to ensure healthy and sustainable development of the oasis, and to maintain the stability of groundwater depth, the current financial resources should be invested in water resources supervision and management. Besides, the construction of agricultural water-saving facilities should be viewed as a long-term development strategy.