Oases provide the most important support to human livelihood and economic activities in drylands. In recent decades, nature and humanity in oases areas have been increasingly integrated, and it is necessary to coordinate the development of the two. This study quantitatively defined the evolutionary phases of the social-ecological system based on varying correlations among agricultural, socioeconomic, and ecological factors. Three different evolutionary phases have been identified in the development of oases in northwestern China since 2000. In the first phase, the groundwater supply increased with agricultural and socioeconomic development. The subsequent phase was characterized as the groundwater supply increased with faster agricultural development. In the final phase, the groundwater supply decreased in response to urban development improvements. As social factors such as population, economic growth, urbanization, and environmental protection became more reliant on groundwater, its contribution to groundwater depletion increased from 8.37% to 76.52%, which further constrained grain production. The findings emphasized that groundwater allocation played a critical role in influencing the development mode of the oasis system. Achieving sustainable social-ecological development requires an integrated and systemic perspective that focuses on the tradeoff between food production, ecological security, water resource security and economic development.